Log Message:
py-h5py: update to 2.8.0

Features
 - allow registration of new drivers
 - add option to track object creation order

Bug fixes
 - allow slices with stop < start as empty
 - improve building with custom hdf5 installation
 - ensure libver defaults to LIBVER_EARLIEST
 - improve handling of float types
 - support non-ascii external paths on py2
 - avoid crashing IPython auto-completer

API changes
 - deprecate ``h5t.available_ftypes``.  This is no longer
   used internally and will be removed in the future.  There is
   no replacement public API.
 - Do not sort fields in compound types.  This is account for changes
   in numpy 1.14.
 - Minimum version of cython is now 0.23