Proposed extensions for Open MPI:
- If MPI_INITLIZED is invoked and MPI is only partially initialized,
wait until MPI is fully initialized before returning.
- If MPI_FINALIZED is invoked and MPI is only partially finalized,
wait until MPI is fully finalized before returning.
- If the ompi_mpix_allow_multi_init MCA param is true, allow MPI_INIT
and MPI_INIT_THREAD to be invoked multiple times without error (MPI
will be safely initialized only the first time it is invoked).