* This change creates an archive containing resource_unpack.c only for
  use in test programs.

* Add proper formatting of example program output.
* Add test to ensure the examples are working.
* Add better handling of Pointer arguments.
* Add better handling of C char * return values.
* Add helper function for C character length.
* Test that the compiler properly support Fortran/C interop at configure
  time.

* The serial code no longer contains dependencies on pio_util.

* This also adds separate documentation, header, Fortran wrappers and
  pkg-config file for the cdi-pio part of the library

* The added pkg.m4 accounts for pkg.m4 sometimes not being available or
  having another version.

* If these are set they already override the corresponding variable.
* Also reduce number of spurious linefeeds in configure.

* Said generic can be replaced with an MPI-specific version, thus
  cleanly separating serialization of meta-data itself and MPI-
  communication.

* It became obsolete with the improvements to make_fint in r1955.