new OpenFOAM June 2017 release: OpenFOAM-v1706 (#4652)

- renamed develop version from 'plus' to 'develop'

- patches now prefixed by corresponding OpenFOAM version number.
  This makes it easier to sort and see what old/junk exists.

- remove MPI_BUFFER_SIZEk env variable (for all openfoam variants).
  The OpenFOAM shell setup addresses this and there is no reason
  to pollute the module environment at this stage.

var/spack/repos/builtin/packages/foam-extend/package.py

@@ -143,7 +143,6 @@ def setup_environment(self, spack_env, run_env):
         run_env.set('WM_PROJECT_DIR', self.projectdir)
         for d in ['wmake', self.archbin]:  # bin already added automatically
             run_env.prepend_path('PATH', join_path(self.projectdir, d))
-        run_env.set('MPI_BUFFER_SIZE', "20000000")
 
     def setup_dependent_environment(self, spack_env, run_env, dependent_spec):
         """Provide location of the OpenFOAM project.