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* This is part of the bits needed to facilitate multiple/incremental
  resource updates on I/O servers.

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

* And make use of this capability in Z-axis.

* 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.