hdf5

Merge pull request #1836 in HDFFV/hdf5 from ~DEROBINS/hdf5_der:develop_minor_pr to develop

* commit '2b1231ddd89dd2f1b59ec9ca1e4e124d7e76f1b5':
  Moved -Wimplicit-procedure gfortran warning to version 4.5 warnings instead of default.