Make default mpi location more generic

git-svn-id: https://svn.mcs.anl.gov/repos/exm/sfw/dev@12711 dc4e9af1-7f46-4ead-bba6-71afc04862de
Clean out old branch in git-svn script

git-svn-id: https://svn.mcs.anl.gov/repos/exm/sfw/dev@12729 dc4e9af1-7f46-4ead-bba6-71afc04862de