hdf5

[svn-r22119] Changes:
  - add VOL implementation for H5O, H5D, and H5T functions
  - update the VOL interface with H5VLget routines
  - make upper level IDs of Type H5I_XXX_PUBLIC
  - bug fixes

Comments:
  - some routines still don't go through VOL but have a workaround so they don't have to at the moment.