hdf5

Merge pull request #1904 in HDFFV/hdf5 from ~BYRN/hdf5_adb:develop to develop

* commit '1efd23ff02b9bc1a3d303d53395245d1366588be':
  Whitespace and HD prefix changes
  fix get gethostname for windows
  OESS-29 Fix HD prefix in perform and enable test compile
  HDFFV-10876 h5dump OPAQUE size should be optional