message: In .travis.yml, on Mac, use the default openmpi package.
  [skip appveyor]
diff: @@ -105,7 +105,7 @@ matrix:
  before_install:
  # No addon for brew yet, have to install OSX packages this way.
  - if [ $TRAVIS_OS_NAME == "osx" ] && [ $MPI == "YES" ]; then
  - brew install open-mpi --without-fortran;
  + brew install open-mpi;
  fi
  # Update environment to find g++ 4.9 installation first.
  