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* And use that if available.

* This should complete the separation of serial and parallel parts
  of the library.

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

* This will allow for later additions of more complex tests.

* This results in an API change for CDI-pio initialization. Users are no longer
  required to specify the number of namespaces in advance.

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

* With the -c switch the test program can also be used for
  benchmarking.

* This is mostly to shut up the compiler.