Merging in latest from upstream (HDFFV/hdf5:refs/heads/develop)
* commit 'aeb145428f5e6bc51742fff031b0cf8cf6fbefbb':
Updated h5trav.c to emit output that doesn't require ddl changes for map support.
Fixed Map API CMake option
Renamed H5Mdelete_key to H5Mdelete and H5Mset to H5Mput.
Added ifdef for intel compilers, __GNUC__ has to be defined for header files which use it to work with intel compilers. This gives a warning for intel compiler about fallthrough, so added a check not to include fallthrough if using intel compilers.
Added the map (H5M) API