hdf5_ep

Merge pull request #1938 in HDFFV/hdf5 from ~BYRN/hdf5_adb:hdf5_1_10 to hdf5_1_10

* commit '36fc437467630d59894deca7aff15b282cb938fb':
  Add clang toolchain
  Fix missing option and incorrect close
  small syntax addition
  Whitespace fix and HD prefix
  Whitespace updates
  Remove obsolete code
  Add missing class name
  Small syntax changes
  Remove unused command block
  Change unused variable to generic form
  HDFFV-10903 merge dev changes to 1.10
  Correct HDF5 options to tristate values
  HDFFV-10903 merge updated changes
  Add new tools lib test folder
  Merge S3 code from develop to 1.10