hdf5_der

Merge pull request #79 in HDFFV/hdf5 from ~DEROBINS/hdf5_der:set_extent_badness_fix to revise_chunks

Merged .gitignore and .gitattributes. We still need to go over .gitattributes more carefully, but that will be a separate JIRA ticket.

* commit 'f2b457cb8502bc4f18596a3aabc0b287f99de9fe':
  Added .gitattributes and .gitignore files (copied from develop)