* Added support for MPI-3.1 features including nonblocking collective I/O,
address manipulation routines, thread-safety for MPI initialization,
pre-init functionality, and new MPI_T routines to look up variables
by name.
* Fortran 2008 bindings are enabled by default and fully supported.
* Added support for the Mellanox MXM InfiniBand interface. (thanks
to Mellanox for the code contribution).
* Added support for the Mellanox HCOLL interface for collectives.
(thanks to Mellanox for the code contribution).
* Significant stability improvements to the MPICH/portals4
implementation.
* Completely revamped RMA infrastructure including several
scalability improvements, performance improvements, and bug fixes.
* Added experimental support for Open Fabrics Interfaces (OFI) version 1.0.0.
https://github.com/ofiwg/libfabric (thanks to Intel for code contribution)
* The Myrinet MX network module, which had a life cyle from 1.1 till
3.1.2, has now been deleted.
* Several other minor bug fixes, memory leak fixes, and code cleanup.
