hdf5_chunking_query_bmr

Merge pull request #635 in HDFFV/hdf5 from GreaterThan-2GB-MPIO to develop

Added some commentary on the fact that 32 bit compilers appear to require actual array arguments to call H5Screate_simple rather than a pointer to a single size_t element.

* commit '22baab211d912f1012057b3a7ae217abd2a44a38':
  Add commentary around calling H5Screate_simple with a single element
  Fix the t_bigio test so that it runs on 32bit machines