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* 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.

* Now autoconf 2.69 and automake 1.11.5 are used.