message: make style, update CHANGELOG
diff: @@ -22,10 +22,6 @@ Improved GPU support
  - Improved multi-GPU MPI communication.
  -Miscellaneous
  --------------
  -- Improved element numbering after uniform mesh refinement.
  -
  Discretization improvements
  ---------------------------
  - Added support for non-conforming prism AMR, including coarsening and parallel
  @@ -43,6 +39,12 @@ Miscellaneous
  the new L2ElementRestriction class. This class also allows for computing
  geometric factors on periodic meshes using partial assembly.
  +- New method Mesh::GetHilbertElementOrdering for sorting mesh elements along
  + the Hilbert curve. The ordering can be used to improve caching and parallel
  + partitioning in non-conforming AMR.
  +
  +- Improved element numbering after uniform mesh refinement.
  +
  Version 4.0, released on May 24, 2019
  =====================================
  