hdf5

Merging in latest from upstream (HDFFV/hdf5:refs/heads/develop)

* commit '2deb953dbbde17712723529c4bca6a2bf3eedf6b':
  Fix for HDFFV-10166 h5watch tests fail randomly to match expected output files (1) Re-structure tests to do one "extend" action at a time (2) Re-try test till max limit before final failure