Fix bug for outputting station names in parallel.

HDF5Ext only has HDF5 file on proc 0.
Added missing stations names to 3d/hex8 Green's fns points file.
Merge branch 'baagaard/feature-output-station-names' into next

* baagaard/feature-output-station-names:
  Added missing stations names to 3d/hex8 Green's fns points file.
  Fix bug for outputting station names in parallel.