Log Message:
Update to OpenMPI 1.6

Disable automatic detection of SGE and SLURM to avoid PLIST divergence.

Changes in OpenMPI 1.6

v1.6 is a major release; it effectively deprecates both the v1.4.x
and v1.5.x series, and replaces v1.4.x as the current "super stable" \ 
series.
A forthcoming v1.7 series will become the new "feature" series.

*All users* -- including production users and downstream providers --
are encouraged to upgrade to v1.6.

Note that v1.6 is ABI compatible with the entire v1.5.x series,
but is not ABI compatible with the v1.4.x series.
See http://www.open-mpi.org/software/ompi/versions/ for a description
of Open MPI's release methodology.

Here is a list of changes in v1.6 as compared to v1.5.5:

- Fix some process affinity issues.  When binding a process, Open MPI
  will now bind to all available hyperthreads in a core (or socket,
  depending on the binding options specified).
  --> Note that "mpirun --bind-to-socket ..." does not work on POWER6-
      and POWER7-based systems with some Linux kernel versions.  See
      the FAQ on the Open MPI web site for more information.
- Add support for ARM5 and ARM6 (in addition to the existing ARM7
  support).  Thanks to Evan Clinton for the patch.
- Minor Mellanox MXM fixes.
- Properly detect FDR10, FDR, and EDR OpenFabrics devices.
- Minor fixes to the mpirun(1) and MPI_Comm_create(3) man pages.
- Prevent segv if COMM_SPAWN_MULTIPLE fails.  Thanks to Fujitsu for
  the patch.
- Disable interposed memory management in fakeroot environments.  This
  fixes a problem in some build environments.
- Minor hwloc updates.
- Array versions of MPI_TEST and MPI_WAIT with a count==0 will now
  return immediately with MPI_SUCCESS.  Thanks to Jeremiah Willcock
  for the suggestion.
- Update VampirTrace to v5.12.2.
- Properly handle forwarding stdin to all processes when "mpirun
  --stdin all" is used.
- Workaround XLC assembly bug.
- OS X Tiger (10.3) has not been supported for a while, so forcibly
  abort configure if we detect it.
- Fix segv in the openib BTL when running on SPARC 64 systems.
- Fix some include file ordering issues on some BSD-based platforms.
  Thanks to Paul Hargove for this (and many, many other) fixes.
- Properly handle .FALSE. return parameter value to attribute copy
  callback functions.
- Fix a bunch of minor C++ API issues; thanks to Fujitsu for the patch.
- Fixed the default hostfile MCA parameter behavior.
- Per the MPI spec, ensure not to touch the port_name parameter to
  MPI_CLOSE_PORT (it's an IN parameter).