hdf5_ep

Merge pull request #317 in HDFFV/hdf5 from ~BYRN/hdf5_adb:hdf5_1_8 to hdf5_1_8

* commit '1653bb14324c2edc1a0c0336eb9f327d4f2e76b9':
  Add option TEST_SHARED_PROGRAMS to disable shared testing by default
  Merge CMake FindMPI changes and CMake documentation from develop
  Disable SHARED VFD tests and remove links_env from defualt list