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* Also rename some functions to include cdi prefix.

* Move functions related to streams to stream.c and
* move functions relating to library as a whole to cdi_int.c.
* Also eliminate STREAM_debug and replace with CDI_Debug.

* Because it holds the namespace the unpacked resource comes from.

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

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