diff --git a/Makefile.in b/Makefile.in
index fdaebeb74d99b0a89dfe3e357859d5a76beabdd0..cb069d4309d3a8eb6e68392b30a14aa8ec5b320e 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.15 from Makefile.am.
+# Makefile.in generated by automake 1.14.1 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2014 Free Software Foundation, Inc.
+# Copyright (C) 1994-2013 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -14,17 +14,7 @@
 
 @SET_MAKE@
 VPATH = @srcdir@
-am__is_gnu_make = { \
-  if test -z '$(MAKELEVEL)'; then \
-    false; \
-  elif test -n '$(MAKE_HOST)'; then \
-    true; \
-  elif test -n '$(MAKE_VERSION)' && test -n '$(CURDIR)'; then \
-    true; \
-  else \
-    false; \
-  fi; \
-}
+am__is_gnu_make = test -n '$(MAKEFILE_LIST)' && test -n '$(MAKELEVEL)'
 am__make_running_with_option = \
   case $${target_option-} in \
       ?) ;; \
@@ -89,6 +79,16 @@ build_triplet = @build@
 host_triplet = @host@
 @ENABLE_CHECK_TRUE@am__append_1 = test
 subdir = .
+DIST_COMMON = INSTALL NEWS README AUTHORS ChangeLog \
+	$(srcdir)/Makefile.in $(srcdir)/Makefile.am \
+	$(top_srcdir)/configure $(am__configure_deps) \
+	$(top_srcdir)/config/config.h.in COPYING config/compile \
+	config/config.guess config/config.sub config/depcomp \
+	config/install-sh config/missing config/ltmain.sh \
+	$(top_srcdir)/config/compile $(top_srcdir)/config/config.guess \
+	$(top_srcdir)/config/config.sub \
+	$(top_srcdir)/config/install-sh $(top_srcdir)/config/ltmain.sh \
+	$(top_srcdir)/config/missing
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/m4/ax_prog_ragel.m4 $(top_srcdir)/m4/libtool.m4 \
@@ -97,8 +97,6 @@ am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
-DIST_COMMON = $(srcdir)/Makefile.am $(top_srcdir)/configure \
-	$(am__configure_deps) $(am__DIST_COMMON)
 am__CONFIG_DISTCLEAN_FILES = config.status config.cache config.log \
  configure.lineno config.status.lineno
 mkinstalldirs = $(install_sh) -d
@@ -161,15 +159,6 @@ ETAGS = etags
 CTAGS = ctags
 CSCOPE = cscope
 DIST_SUBDIRS = src test doc examples
-am__DIST_COMMON = $(srcdir)/Makefile.in $(top_srcdir)/config/compile \
-	$(top_srcdir)/config/config.guess \
-	$(top_srcdir)/config/config.h.in \
-	$(top_srcdir)/config/config.sub \
-	$(top_srcdir)/config/install-sh $(top_srcdir)/config/ltmain.sh \
-	$(top_srcdir)/config/missing AUTHORS COPYING ChangeLog INSTALL \
-	NEWS README config/compile config/config.guess \
-	config/config.sub config/depcomp config/install-sh \
-	config/ltmain.sh config/missing
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
 distdir = $(PACKAGE)-$(VERSION)
 top_distdir = $(distdir)
@@ -398,6 +387,7 @@ $(srcdir)/Makefile.in: @MAINTAINER_MODE_TRUE@ $(srcdir)/Makefile.am  $(am__confi
 	echo ' cd $(top_srcdir) && $(AUTOMAKE) --gnu Makefile'; \
 	$(am__cd) $(top_srcdir) && \
 	  $(AUTOMAKE) --gnu Makefile
+.PRECIOUS: Makefile
 Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
 	@case '$?' in \
 	  *config.status*) \
@@ -628,15 +618,15 @@ dist-xz: distdir
 	$(am__post_remove_distdir)
 
 dist-tarZ: distdir
-	@echo WARNING: "Support for distribution archives compressed with" \
-		       "legacy program 'compress' is deprecated." >&2
+	@echo WARNING: "Support for shar distribution archives is" \
+	               "deprecated." >&2
 	@echo WARNING: "It will be removed altogether in Automake 2.0" >&2
 	tardir=$(distdir) && $(am__tar) | compress -c >$(distdir).tar.Z
 	$(am__post_remove_distdir)
 
 dist-shar: distdir
-	@echo WARNING: "Support for shar distribution archives is" \
-	               "deprecated." >&2
+	@echo WARNING: "Support for distribution archives compressed with" \
+		       "legacy program 'compress' is deprecated." >&2
 	@echo WARNING: "It will be removed altogether in Automake 2.0" >&2
 	shar $(distdir) | GZIP=$(GZIP_ENV) gzip -c >$(distdir).shar.gz
 	$(am__post_remove_distdir)
@@ -672,17 +662,17 @@ distcheck: dist
 	esac
 	chmod -R a-w $(distdir)
 	chmod u+w $(distdir)
-	mkdir $(distdir)/_build $(distdir)/_build/sub $(distdir)/_inst
+	mkdir $(distdir)/_build $(distdir)/_inst
 	chmod a-w $(distdir)
 	test -d $(distdir)/_build || exit 0; \
 	dc_install_base=`$(am__cd) $(distdir)/_inst && pwd | sed -e 's,^[^:\\/]:[\\/],/,'` \
 	  && dc_destdir="$${TMPDIR-/tmp}/am-dc-$$$$/" \
 	  && am__cwd=`pwd` \
-	  && $(am__cd) $(distdir)/_build/sub \
-	  && ../../configure \
+	  && $(am__cd) $(distdir)/_build \
+	  && ../configure \
 	    $(AM_DISTCHECK_CONFIGURE_FLAGS) \
 	    $(DISTCHECK_CONFIGURE_FLAGS) \
-	    --srcdir=../.. --prefix="$$dc_install_base" \
+	    --srcdir=.. --prefix="$$dc_install_base" \
 	  && $(MAKE) $(AM_MAKEFLAGS) \
 	  && $(MAKE) $(AM_MAKEFLAGS) dvi \
 	  && $(MAKE) $(AM_MAKEFLAGS) check \
@@ -859,8 +849,6 @@ uninstall-am:
 	mostlyclean-libtool pdf pdf-am ps ps-am tags tags-am uninstall \
 	uninstall-am
 
-.PRECIOUS: Makefile
-
 
 doc:
 	cd doc && $(MAKE) $(AM_MAKEFLAGS) doc
diff --git a/aclocal.m4 b/aclocal.m4
index cc0029eb7f81d74862d26e3d0d8e967179543a8c..f5ec97e99a0966653164ddf45177bbaa7659427c 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1,6 +1,6 @@
-# generated automatically by aclocal 1.15 -*- Autoconf -*-
+# generated automatically by aclocal 1.14.1 -*- Autoconf -*-
 
-# Copyright (C) 1996-2014 Free Software Foundation, Inc.
+# Copyright (C) 1996-2013 Free Software Foundation, Inc.
 
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -20,7 +20,7 @@ You have another version of autoconf.  It may work, but is not guaranteed to.
 If you have problems, you may need to regenerate the build system entirely.
 To do so, use the procedure documented by the package, typically 'autoreconf'.])])
 
-# Copyright (C) 2002-2014 Free Software Foundation, Inc.
+# Copyright (C) 2002-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -32,10 +32,10 @@ To do so, use the procedure documented by the package, typically 'autoreconf'.])
 # generated from the m4 files accompanying Automake X.Y.
 # (This private macro should not be called outside this file.)
 AC_DEFUN([AM_AUTOMAKE_VERSION],
-[am__api_version='1.15'
+[am__api_version='1.14'
 dnl Some users find AM_AUTOMAKE_VERSION and mistake it for a way to
 dnl require some minimum version.  Point them to the right macro.
-m4_if([$1], [1.15], [],
+m4_if([$1], [1.14.1], [],
       [AC_FATAL([Do not call $0, use AM_INIT_AUTOMAKE([$1]).])])dnl
 ])
 
@@ -51,14 +51,14 @@ m4_define([_AM_AUTOCONF_VERSION], [])
 # Call AM_AUTOMAKE_VERSION and AM_AUTOMAKE_VERSION so they can be traced.
 # This function is AC_REQUIREd by AM_INIT_AUTOMAKE.
 AC_DEFUN([AM_SET_CURRENT_AUTOMAKE_VERSION],
-[AM_AUTOMAKE_VERSION([1.15])dnl
+[AM_AUTOMAKE_VERSION([1.14.1])dnl
 m4_ifndef([AC_AUTOCONF_VERSION],
   [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
 _AM_AUTOCONF_VERSION(m4_defn([AC_AUTOCONF_VERSION]))])
 
 # AM_AUX_DIR_EXPAND                                         -*- Autoconf -*-
 
-# Copyright (C) 2001-2014 Free Software Foundation, Inc.
+# Copyright (C) 2001-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -103,14 +103,15 @@ _AM_AUTOCONF_VERSION(m4_defn([AC_AUTOCONF_VERSION]))])
 # configured tree to be moved without reconfiguration.
 
 AC_DEFUN([AM_AUX_DIR_EXPAND],
-[AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT])dnl
-# Expand $ac_aux_dir to an absolute path.
-am_aux_dir=`cd "$ac_aux_dir" && pwd`
+[dnl Rely on autoconf to set up CDPATH properly.
+AC_PREREQ([2.50])dnl
+# expand $ac_aux_dir to an absolute path
+am_aux_dir=`cd $ac_aux_dir && pwd`
 ])
 
 # AM_CONDITIONAL                                            -*- Autoconf -*-
 
-# Copyright (C) 1997-2014 Free Software Foundation, Inc.
+# Copyright (C) 1997-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -141,7 +142,7 @@ AC_CONFIG_COMMANDS_PRE(
 Usually this means the macro was only invoked conditionally.]])
 fi])])
 
-# Copyright (C) 1999-2014 Free Software Foundation, Inc.
+# Copyright (C) 1999-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -332,7 +333,7 @@ _AM_SUBST_NOTMAKE([am__nodep])dnl
 
 # Generate code to set up dependency tracking.              -*- Autoconf -*-
 
-# Copyright (C) 1999-2014 Free Software Foundation, Inc.
+# Copyright (C) 1999-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -408,7 +409,7 @@ AC_DEFUN([AM_OUTPUT_DEPENDENCY_COMMANDS],
 
 # Do all the work for Automake.                             -*- Autoconf -*-
 
-# Copyright (C) 1996-2014 Free Software Foundation, Inc.
+# Copyright (C) 1996-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -498,8 +499,8 @@ AC_REQUIRE([AC_PROG_MKDIR_P])dnl
 # <http://lists.gnu.org/archive/html/automake/2012-07/msg00001.html>
 # <http://lists.gnu.org/archive/html/automake/2012-07/msg00014.html>
 AC_SUBST([mkdir_p], ['$(MKDIR_P)'])
-# We need awk for the "check" target (and possibly the TAP driver).  The
-# system "awk" is bad on some platforms.
+# We need awk for the "check" target.  The system "awk" is bad on
+# some platforms.
 AC_REQUIRE([AC_PROG_AWK])dnl
 AC_REQUIRE([AC_PROG_MAKE_SET])dnl
 AC_REQUIRE([AM_SET_LEADING_DOT])dnl
@@ -572,11 +573,7 @@ to "yes", and re-run configure.
 END
     AC_MSG_ERROR([Your 'rm' program is bad, sorry.])
   fi
-fi
-dnl The trailing newline in this macro's definition is deliberate, for
-dnl backward compatibility and to allow trailing 'dnl'-style comments
-dnl after the AM_INIT_AUTOMAKE invocation. See automake bug#16841.
-])
+fi])
 
 dnl Hook into '_AC_COMPILER_EXEEXT' early to learn its expansion.  Do not
 dnl add the conditional right here, as _AC_COMPILER_EXEEXT may be further
@@ -605,7 +602,7 @@ for _am_header in $config_headers :; do
 done
 echo "timestamp for $_am_arg" >`AS_DIRNAME(["$_am_arg"])`/stamp-h[]$_am_stamp_count])
 
-# Copyright (C) 2001-2014 Free Software Foundation, Inc.
+# Copyright (C) 2001-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -616,7 +613,7 @@ echo "timestamp for $_am_arg" >`AS_DIRNAME(["$_am_arg"])`/stamp-h[]$_am_stamp_co
 # Define $install_sh.
 AC_DEFUN([AM_PROG_INSTALL_SH],
 [AC_REQUIRE([AM_AUX_DIR_EXPAND])dnl
-if test x"${install_sh+set}" != xset; then
+if test x"${install_sh}" != xset; then
   case $am_aux_dir in
   *\ * | *\	*)
     install_sh="\${SHELL} '$am_aux_dir/install-sh'" ;;
@@ -626,7 +623,7 @@ if test x"${install_sh+set}" != xset; then
 fi
 AC_SUBST([install_sh])])
 
-# Copyright (C) 2003-2014 Free Software Foundation, Inc.
+# Copyright (C) 2003-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -648,7 +645,7 @@ AC_SUBST([am__leading_dot])])
 # Add --enable-maintainer-mode option to configure.         -*- Autoconf -*-
 # From Jim Meyering
 
-# Copyright (C) 1996-2014 Free Software Foundation, Inc.
+# Copyright (C) 1996-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -683,7 +680,7 @@ AC_MSG_CHECKING([whether to enable maintainer-specific portions of Makefiles])
 
 # Check to see how 'make' treats includes.	            -*- Autoconf -*-
 
-# Copyright (C) 2001-2014 Free Software Foundation, Inc.
+# Copyright (C) 2001-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -733,7 +730,7 @@ rm -f confinc confmf
 
 # Fake the existence of programs that GNU maintainers use.  -*- Autoconf -*-
 
-# Copyright (C) 1997-2014 Free Software Foundation, Inc.
+# Copyright (C) 1997-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -772,7 +769,7 @@ fi
 
 # Helper functions for option handling.                     -*- Autoconf -*-
 
-# Copyright (C) 2001-2014 Free Software Foundation, Inc.
+# Copyright (C) 2001-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -801,7 +798,7 @@ AC_DEFUN([_AM_SET_OPTIONS],
 AC_DEFUN([_AM_IF_OPTION],
 [m4_ifset(_AM_MANGLE_OPTION([$1]), [$2], [$3])])
 
-# Copyright (C) 1999-2014 Free Software Foundation, Inc.
+# Copyright (C) 1999-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -848,7 +845,7 @@ AC_LANG_POP([C])])
 # For backward compatibility.
 AC_DEFUN_ONCE([AM_PROG_CC_C_O], [AC_REQUIRE([AC_PROG_CC])])
 
-# Copyright (C) 2001-2014 Free Software Foundation, Inc.
+# Copyright (C) 2001-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -867,7 +864,7 @@ AC_DEFUN([AM_RUN_LOG],
 
 # Check to make sure that the build environment is sane.    -*- Autoconf -*-
 
-# Copyright (C) 1996-2014 Free Software Foundation, Inc.
+# Copyright (C) 1996-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -948,7 +945,7 @@ AC_CONFIG_COMMANDS_PRE(
 rm -f conftest.file
 ])
 
-# Copyright (C) 2009-2014 Free Software Foundation, Inc.
+# Copyright (C) 2009-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1008,7 +1005,7 @@ AC_SUBST([AM_BACKSLASH])dnl
 _AM_SUBST_NOTMAKE([AM_BACKSLASH])dnl
 ])
 
-# Copyright (C) 2001-2014 Free Software Foundation, Inc.
+# Copyright (C) 2001-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1036,7 +1033,7 @@ fi
 INSTALL_STRIP_PROGRAM="\$(install_sh) -c -s"
 AC_SUBST([INSTALL_STRIP_PROGRAM])])
 
-# Copyright (C) 2006-2014 Free Software Foundation, Inc.
+# Copyright (C) 2006-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1055,7 +1052,7 @@ AC_DEFUN([AM_SUBST_NOTMAKE], [_AM_SUBST_NOTMAKE($@)])
 
 # Check how to create a tarball.                            -*- Autoconf -*-
 
-# Copyright (C) 2004-2014 Free Software Foundation, Inc.
+# Copyright (C) 2004-2013 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
diff --git a/doc/Makefile.in b/doc/Makefile.in
index ca724bbbf38743117d4f621f9f677a47855e4205..b01b4a9aa06c566e412355f85a81113c769fa161 100644
--- a/doc/Makefile.in
+++ b/doc/Makefile.in
@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.15 from Makefile.am.
+# Makefile.in generated by automake 1.14.1 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2014 Free Software Foundation, Inc.
+# Copyright (C) 1994-2013 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -14,17 +14,7 @@
 
 @SET_MAKE@
 VPATH = @srcdir@
-am__is_gnu_make = { \
-  if test -z '$(MAKELEVEL)'; then \
-    false; \
-  elif test -n '$(MAKE_HOST)'; then \
-    true; \
-  elif test -n '$(MAKE_VERSION)' && test -n '$(CURDIR)'; then \
-    true; \
-  else \
-    false; \
-  fi; \
-}
+am__is_gnu_make = test -n '$(MAKEFILE_LIST)' && test -n '$(MAKELEVEL)'
 am__make_running_with_option = \
   case $${target_option-} in \
       ?) ;; \
@@ -88,6 +78,8 @@ POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
 subdir = doc
+DIST_COMMON = $(srcdir)/Makefile.in $(srcdir)/Makefile.am \
+	$(srcdir)/Doxyfile.in
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/m4/ax_prog_ragel.m4 $(top_srcdir)/m4/libtool.m4 \
@@ -96,7 +88,6 @@ am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
-DIST_COMMON = $(srcdir)/Makefile.am $(am__DIST_COMMON)
 mkinstalldirs = $(install_sh) -d
 CONFIG_HEADER = $(top_builddir)/config/config.h
 CONFIG_CLEAN_FILES = Doxyfile
@@ -121,7 +112,6 @@ am__can_run_installinfo = \
     *) (install-info --version) >/dev/null 2>&1;; \
   esac
 am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) $(LISP)
-am__DIST_COMMON = $(srcdir)/Doxyfile.in $(srcdir)/Makefile.in
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
 ACLOCAL = @ACLOCAL@
 AMTAR = @AMTAR@
@@ -304,6 +294,7 @@ $(srcdir)/Makefile.in: @MAINTAINER_MODE_TRUE@ $(srcdir)/Makefile.am  $(am__confi
 	echo ' cd $(top_srcdir) && $(AUTOMAKE) --gnu doc/Makefile'; \
 	$(am__cd) $(top_srcdir) && \
 	  $(AUTOMAKE) --gnu doc/Makefile
+.PRECIOUS: Makefile
 Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
 	@case '$?' in \
 	  *config.status*) \
@@ -400,8 +391,8 @@ distclean-generic:
 maintainer-clean-generic:
 	@echo "This command is intended for maintainers to use"
 	@echo "it deletes files that may require special tools to rebuild."
-@DX_COND_doc_FALSE@mostlyclean-local:
 @DX_COND_doc_FALSE@install-data-local:
+@DX_COND_doc_FALSE@mostlyclean-local:
 clean: clean-am
 
 clean-am: clean-generic clean-libtool mostlyclean-am
@@ -484,8 +475,6 @@ uninstall-am:
 	mostlyclean-libtool mostlyclean-local pdf pdf-am ps ps-am \
 	tags-am uninstall uninstall-am
 
-.PRECIOUS: Makefile
-
 
 @DX_COND_doc_TRUE@@DX_COND_pdf_TRUE@doxygen-pdf: @DX_DOCDIR@/@PACKAGE@.pdf
 
diff --git a/examples/Makefile.am b/examples/Makefile.am
index 5b8a9f823ea295028138f3eb0bfe21ccc87197e3..5029241311695f7a402cd01184047cde3ac0de10 100644
--- a/examples/Makefile.am
+++ b/examples/Makefile.am
@@ -5,6 +5,7 @@ bin_PROGRAMS = \
 	time_calculus \
 	model_integration \
 	example \
+	example_hl \
 	duration \
 	output_control \
 	recurrence \
@@ -29,6 +30,10 @@ example_SOURCES = example.f90
 example_LDADD = ../src/libmtime.la
 example_LDFLAGS=
 
+example_hl_SOURCES = example_hl.f90
+example_hl_LDADD = ../src/libmtime.la
+example_hl_LDFLAGS=
+
 duration_SOURCES = duration.f90
 duration_LDADD = ../src/libmtime.la
 duration_LDFLAGS=
diff --git a/examples/Makefile.in b/examples/Makefile.in
index cbbbffffc937c5906d88e648b48dc8d2f33a9faa..529e4c00339ffc5a95dd3c009d288f955219eb11 100644
--- a/examples/Makefile.in
+++ b/examples/Makefile.in
@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.15 from Makefile.am.
+# Makefile.in generated by automake 1.14.1 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2014 Free Software Foundation, Inc.
+# Copyright (C) 1994-2013 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -15,17 +15,7 @@
 @SET_MAKE@
 
 VPATH = @srcdir@
-am__is_gnu_make = { \
-  if test -z '$(MAKELEVEL)'; then \
-    false; \
-  elif test -n '$(MAKE_HOST)'; then \
-    true; \
-  elif test -n '$(MAKE_VERSION)' && test -n '$(CURDIR)'; then \
-    true; \
-  else \
-    false; \
-  fi; \
-}
+am__is_gnu_make = test -n '$(MAKEFILE_LIST)' && test -n '$(MAKELEVEL)'
 am__make_running_with_option = \
   case $${target_option-} in \
       ?) ;; \
@@ -89,11 +79,14 @@ POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
 bin_PROGRAMS = time_calculus$(EXEEXT) model_integration$(EXEEXT) \
-	example$(EXEEXT) duration$(EXEEXT) output_control$(EXEEXT) \
-	recurrence$(EXEEXT) repetitor$(EXEEXT) tas$(EXEEXT) \
-	uniq$(EXEEXT) modulo$(EXEEXT) comp_weights$(EXEEXT) \
-	callback_test$(EXEEXT) iconatm$(EXEEXT) iconoce$(EXEEXT)
+	example$(EXEEXT) example_hl$(EXEEXT) duration$(EXEEXT) \
+	output_control$(EXEEXT) recurrence$(EXEEXT) repetitor$(EXEEXT) \
+	tas$(EXEEXT) uniq$(EXEEXT) modulo$(EXEEXT) \
+	comp_weights$(EXEEXT) callback_test$(EXEEXT) iconatm$(EXEEXT) \
+	iconoce$(EXEEXT)
 subdir = examples
+DIST_COMMON = $(srcdir)/Makefile.in $(srcdir)/Makefile.am \
+	$(top_srcdir)/config/depcomp
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/m4/ax_prog_ragel.m4 $(top_srcdir)/m4/libtool.m4 \
@@ -102,7 +95,6 @@ am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
-DIST_COMMON = $(srcdir)/Makefile.am $(am__DIST_COMMON)
 mkinstalldirs = $(install_sh) -d
 CONFIG_HEADER = $(top_builddir)/config/config.h
 CONFIG_CLEAN_FILES =
@@ -137,6 +129,12 @@ example_DEPENDENCIES = ../src/libmtime.la
 example_LINK = $(LIBTOOL) $(AM_V_lt) --tag=FC $(AM_LIBTOOLFLAGS) \
 	$(LIBTOOLFLAGS) --mode=link $(FCLD) $(AM_FCFLAGS) $(FCFLAGS) \
 	$(example_LDFLAGS) $(LDFLAGS) -o $@
+am_example_hl_OBJECTS = example_hl.$(OBJEXT)
+example_hl_OBJECTS = $(am_example_hl_OBJECTS)
+example_hl_DEPENDENCIES = ../src/libmtime.la
+example_hl_LINK = $(LIBTOOL) $(AM_V_lt) --tag=FC $(AM_LIBTOOLFLAGS) \
+	$(LIBTOOLFLAGS) --mode=link $(FCLD) $(AM_FCFLAGS) $(FCFLAGS) \
+	$(example_hl_LDFLAGS) $(LDFLAGS) -o $@
 am_iconatm_OBJECTS = iconatm.$(OBJEXT)
 iconatm_OBJECTS = $(am_iconatm_OBJECTS)
 iconatm_DEPENDENCIES = ../src/libmtime.la
@@ -250,17 +248,19 @@ am__v_FCLD_ = $(am__v_FCLD_@AM_DEFAULT_V@)
 am__v_FCLD_0 = @echo "  FCLD    " $@;
 am__v_FCLD_1 = 
 SOURCES = $(callback_test_SOURCES) $(comp_weights_SOURCES) \
-	$(duration_SOURCES) $(example_SOURCES) $(iconatm_SOURCES) \
-	$(iconoce_SOURCES) $(model_integration_SOURCES) \
-	$(modulo_SOURCES) $(output_control_SOURCES) \
-	$(recurrence_SOURCES) $(repetitor_SOURCES) $(tas_SOURCES) \
-	$(time_calculus_SOURCES) $(uniq_SOURCES)
+	$(duration_SOURCES) $(example_SOURCES) $(example_hl_SOURCES) \
+	$(iconatm_SOURCES) $(iconoce_SOURCES) \
+	$(model_integration_SOURCES) $(modulo_SOURCES) \
+	$(output_control_SOURCES) $(recurrence_SOURCES) \
+	$(repetitor_SOURCES) $(tas_SOURCES) $(time_calculus_SOURCES) \
+	$(uniq_SOURCES)
 DIST_SOURCES = $(callback_test_SOURCES) $(comp_weights_SOURCES) \
-	$(duration_SOURCES) $(example_SOURCES) $(iconatm_SOURCES) \
-	$(iconoce_SOURCES) $(model_integration_SOURCES) \
-	$(modulo_SOURCES) $(output_control_SOURCES) \
-	$(recurrence_SOURCES) $(repetitor_SOURCES) $(tas_SOURCES) \
-	$(time_calculus_SOURCES) $(uniq_SOURCES)
+	$(duration_SOURCES) $(example_SOURCES) $(example_hl_SOURCES) \
+	$(iconatm_SOURCES) $(iconoce_SOURCES) \
+	$(model_integration_SOURCES) $(modulo_SOURCES) \
+	$(output_control_SOURCES) $(recurrence_SOURCES) \
+	$(repetitor_SOURCES) $(tas_SOURCES) $(time_calculus_SOURCES) \
+	$(uniq_SOURCES)
 am__can_run_installinfo = \
   case $$AM_UPDATE_INFO_DIR in \
     n|no|NO) false;; \
@@ -285,7 +285,6 @@ am__define_uniq_tagged_files = \
   done | $(am__uniquify_input)`
 ETAGS = etags
 CTAGS = ctags
-am__DIST_COMMON = $(srcdir)/Makefile.in $(top_srcdir)/config/depcomp
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
 ACLOCAL = @ACLOCAL@
 AMTAR = @AMTAR@
@@ -451,6 +450,9 @@ model_integration_LDFLAGS =
 example_SOURCES = example.f90
 example_LDADD = ../src/libmtime.la
 example_LDFLAGS = 
+example_hl_SOURCES = example_hl.f90
+example_hl_LDADD = ../src/libmtime.la
+example_hl_LDFLAGS = 
 duration_SOURCES = duration.f90
 duration_LDADD = ../src/libmtime.la
 duration_LDFLAGS = 
@@ -500,6 +502,7 @@ $(srcdir)/Makefile.in: @MAINTAINER_MODE_TRUE@ $(srcdir)/Makefile.am  $(am__confi
 	echo ' cd $(top_srcdir) && $(AUTOMAKE) --gnu examples/Makefile'; \
 	$(am__cd) $(top_srcdir) && \
 	  $(AUTOMAKE) --gnu examples/Makefile
+.PRECIOUS: Makefile
 Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
 	@case '$?' in \
 	  *config.status*) \
@@ -583,6 +586,10 @@ example$(EXEEXT): $(example_OBJECTS) $(example_DEPENDENCIES) $(EXTRA_example_DEP
 	@rm -f example$(EXEEXT)
 	$(AM_V_FCLD)$(example_LINK) $(example_OBJECTS) $(example_LDADD) $(LIBS)
 
+example_hl$(EXEEXT): $(example_hl_OBJECTS) $(example_hl_DEPENDENCIES) $(EXTRA_example_hl_DEPENDENCIES) 
+	@rm -f example_hl$(EXEEXT)
+	$(AM_V_FCLD)$(example_hl_LINK) $(example_hl_OBJECTS) $(example_hl_LDADD) $(LIBS)
+
 iconatm$(EXEEXT): $(iconatm_OBJECTS) $(iconatm_DEPENDENCIES) $(EXTRA_iconatm_DEPENDENCIES) 
 	@rm -f iconatm$(EXEEXT)
 	$(AM_V_FCLD)$(iconatm_LINK) $(iconatm_OBJECTS) $(iconatm_LDADD) $(LIBS)
@@ -875,8 +882,6 @@ uninstall-am: uninstall-binPROGRAMS
 	mostlyclean-generic mostlyclean-libtool pdf pdf-am ps ps-am \
 	tags tags-am uninstall uninstall-am uninstall-binPROGRAMS
 
-.PRECIOUS: Makefile
-
 
 mo_kind.$(OBJEXT): mo_kind.f90
 mo_output_event_types.$(OBJEXT):  mo_output_event_types.f90 mo_kind.$(OBJEXT)
diff --git a/examples/example_hl.f90 b/examples/example_hl.f90
new file mode 100644
index 0000000000000000000000000000000000000000..2fc1871348d2190ad8ef6b4b890b986386a281fe
--- /dev/null
+++ b/examples/example_hl.f90
@@ -0,0 +1,59 @@
+PROGRAM example
+
+  USE mtime,    ONLY: setCalendar, PROLEPTIC_GREGORIAN  
+  USE mtime_hl, ONLY: t_datetime, t_timedelta
+  
+  IMPLICIT NONE
+  
+  TYPE(t_datetime)  :: dt, dt2, dt3
+  TYPE(t_timedelta) :: td
+
+  WRITE (0,*) "example_hl : test example"
+
+  WRITE (0,*) "  setting calendar."
+  CALL setCalendar(PROLEPTIC_GREGORIAN)
+
+  ! Instead of:  TYPE(datetime), POINTER :: dt
+  !              dt => newDatetime("1970-01-01T00:00:00")
+  !                [...]
+  !              CALL deallocateDatetime(dt)
+
+  ! TYPE(t_datetime)  :: dt
+  WRITE (0,*) "  testing assignment of t_datetime."
+  dt = "1970-01-01T00:00:00"
+
+  ! Instead of:  TYPE(timedelta), POINTER :: td
+  !              td => newTimeDelta("PT1H1M1S")
+  !                [...]
+  !              CALL deallocateTimedelta(td)
+
+  ! TYPE(t_timedelta) :: td
+  WRITE (0,*) "  testing assignment of t_timedelta."
+  td = "PT1H1M1S"
+
+  ! Instead of:  CALL datetimeToString(dt, dstring1)
+  !              CALL timedeltaToString(td, dstring2)
+  !              WRITE (0,*) "compute ", dstring1, " + ", dstring2
+
+  WRITE (0,*) "compute ", dt%to_string(), " + ", td%to_string()
+
+  ! Adding time intervals is unchanged:
+
+  dt = dt + td
+  WRITE (0,*) "result: ", dt%to_string()
+
+  ! --- Further examples:
+
+  ! subtraction of two dates
+  dt2 = "1970-01-01T00:00:00"
+  td = dt-dt2
+  WRITE (0,*) "subtraction of dates: time delta: ", td%to_string()
+
+  ! comparison of dates
+  dt  = "1970-01-01T00:00:00"
+  dt2 = "1970-01-01T00:00:00"
+  WRITE (0,*) dt%to_string(), " == ", dt2%to_string(), ": ", (dt == dt2)
+  dt3 = "1970-01-01T00:00:01"
+  WRITE (0,*) dt%to_string(), " == ", dt3%to_string(), ": ", (dt == dt3)
+  
+END PROGRAM example
diff --git a/src/Makefile.in b/src/Makefile.in
index 61d9afa48f83408a3b9513114ccb228dd342288b..e0d85be506c548f14431364e6cd38968240c4542 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.15 from Makefile.am.
+# Makefile.in generated by automake 1.14.1 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2014 Free Software Foundation, Inc.
+# Copyright (C) 1994-2013 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -15,17 +15,7 @@
 @SET_MAKE@
 
 VPATH = @srcdir@
-am__is_gnu_make = { \
-  if test -z '$(MAKELEVEL)'; then \
-    false; \
-  elif test -n '$(MAKE_HOST)'; then \
-    true; \
-  elif test -n '$(MAKE_VERSION)' && test -n '$(CURDIR)'; then \
-    true; \
-  else \
-    false; \
-  fi; \
-}
+am__is_gnu_make = test -n '$(MAKEFILE_LIST)' && test -n '$(MAKELEVEL)'
 am__make_running_with_option = \
   case $${target_option-} in \
       ?) ;; \
@@ -89,6 +79,8 @@ POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
 subdir = src
+DIST_COMMON = $(srcdir)/Makefile.in $(srcdir)/Makefile.am \
+	$(top_srcdir)/config/depcomp
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/m4/ax_prog_ragel.m4 $(top_srcdir)/m4/libtool.m4 \
@@ -97,7 +89,6 @@ am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
-DIST_COMMON = $(srcdir)/Makefile.am $(am__DIST_COMMON)
 mkinstalldirs = $(install_sh) -d
 CONFIG_HEADER = $(top_builddir)/config/config.h
 CONFIG_CLEAN_FILES =
@@ -218,7 +209,6 @@ am__define_uniq_tagged_files = \
   done | $(am__uniquify_input)`
 ETAGS = etags
 CTAGS = ctags
-am__DIST_COMMON = $(srcdir)/Makefile.in $(top_srcdir)/config/depcomp
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
 ACLOCAL = @ACLOCAL@
 AMTAR = @AMTAR@
@@ -424,6 +414,7 @@ $(srcdir)/Makefile.in: @MAINTAINER_MODE_TRUE@ $(srcdir)/Makefile.am  $(am__confi
 	echo ' cd $(top_srcdir) && $(AUTOMAKE) --gnu src/Makefile'; \
 	$(am__cd) $(top_srcdir) && \
 	  $(AUTOMAKE) --gnu src/Makefile
+.PRECIOUS: Makefile
 Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
 	@case '$?' in \
 	  *config.status*) \
@@ -746,8 +737,6 @@ uninstall-am: uninstall-libLTLIBRARIES
 	mostlyclean-generic mostlyclean-libtool pdf pdf-am ps ps-am \
 	tags tags-am uninstall uninstall-am uninstall-libLTLIBRARIES
 
-.PRECIOUS: Makefile
-
 
 libmtime_hl.o: libtime_hl.f90 libtime.o
 
diff --git a/test/Makefile.in b/test/Makefile.in
index 855694e7dfcc0b7f80e67c1d6bc21c1ae2996b36..2f128886a2a132d36e18aa11061673ec6029c0a9 100644
--- a/test/Makefile.in
+++ b/test/Makefile.in
@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.15 from Makefile.am.
+# Makefile.in generated by automake 1.14.1 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2014 Free Software Foundation, Inc.
+# Copyright (C) 1994-2013 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -16,17 +16,7 @@
 
 
 VPATH = @srcdir@
-am__is_gnu_make = { \
-  if test -z '$(MAKELEVEL)'; then \
-    false; \
-  elif test -n '$(MAKE_HOST)'; then \
-    true; \
-  elif test -n '$(MAKE_VERSION)' && test -n '$(CURDIR)'; then \
-    true; \
-  else \
-    false; \
-  fi; \
-}
+am__is_gnu_make = test -n '$(MAKEFILE_LIST)' && test -n '$(MAKELEVEL)'
 am__make_running_with_option = \
   case $${target_option-} in \
       ?) ;; \
@@ -94,6 +84,8 @@ noinst_PROGRAMS = $(am__EXEEXT_1)
 @ENABLE_CHECK_TRUE@am__append_2 = test_runner
 @ENABLE_CHECK_TRUE@am__append_3 = test_runner
 subdir = test
+DIST_COMMON = $(srcdir)/Makefile.in $(srcdir)/Makefile.am \
+	$(top_srcdir)/config/depcomp
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/m4/ax_prog_ragel.m4 $(top_srcdir)/m4/libtool.m4 \
@@ -102,7 +94,6 @@ am__aclocal_m4_deps = $(top_srcdir)/m4/ax_prog_doxygen.m4 \
 	$(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
-DIST_COMMON = $(srcdir)/Makefile.am $(am__DIST_COMMON)
 mkinstalldirs = $(install_sh) -d
 CONFIG_HEADER = $(top_builddir)/config/config.h
 CONFIG_CLEAN_FILES =
@@ -199,7 +190,6 @@ am__define_uniq_tagged_files = \
   done | $(am__uniquify_input)`
 ETAGS = etags
 CTAGS = ctags
-am__DIST_COMMON = $(srcdir)/Makefile.in $(top_srcdir)/config/depcomp
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
 ACLOCAL = @ACLOCAL@
 AMTAR = @AMTAR@
@@ -389,6 +379,7 @@ $(srcdir)/Makefile.in: @MAINTAINER_MODE_TRUE@ $(srcdir)/Makefile.am  $(am__confi
 	echo ' cd $(top_srcdir) && $(AUTOMAKE) --gnu test/Makefile'; \
 	$(am__cd) $(top_srcdir) && \
 	  $(AUTOMAKE) --gnu test/Makefile
+.PRECIOUS: Makefile
 Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
 	@case '$?' in \
 	  *config.status*) \
@@ -734,8 +725,6 @@ uninstall-am:
 	mostlyclean-generic mostlyclean-libtool pdf pdf-am ps ps-am \
 	tags tags-am uninstall uninstall-am
 
-.PRECIOUS: Makefile
-
 
 ac-local: check
 .PHONY :check