hdf5

Merge pull request #1313 in HDFFV/hdf5 from ~DEROBINS/hdf5_der:vol_tweaks to develop

* commit 'ee12aff2ca89e92b99590f29096794a84c6bacdc':
  Removed a couple of extraneous commas from VOL example.
  Cleaned up VOL example.
  Updated MANIFEST file.
  Fixed VOL example to use a platform-independent format specifier for size_t.