oshmem: rename global variables with prefix
btl sm: restore btl_sm_have_knem_support MCA param

Somehow, this MCA param was accidentally dropped after v1.6.5.  Thanks
to Gus Correa for bringing this matter to our attention.

Also moving some MCA params down from level 9 to levels 4/5.
btl sm: error if knem support is requested and cannot be activated

Restore the functionality to error out (and show a helpful message) if
knem support is requested by is either not compiled in or cannot be
activated.

Thanks to Gus Correa for bringing the matter to our attention.
Update the orterun man page
Fix building system: correct libltdl check for advise capability.
Quick pass over the sm-knem code, indent fixes
Fix libltdl VPATH configuration.
Merge pull request #240 from artpol84/ltdl_advise_fix

Fix building system: correct libltdl check for advise capability.
OSHMEM: spml ikrit: complete puts b4 memheap destruction

Force completion of all puts before deregestering memheap/bss memory

Fixes a possible race condition where put request completion callback
is called when request context is already cleared.

Change-Id: I7ed887ec0b03a66ce5d3076a7edcf64061f57370
Merge branch 'topic/oshmem_spml_ikrit_race'
Cleanup the orterun man page per review by Gus Correa
MTL MXM cleanup: unnecessary OMPI_MTL_MXM_CONNECT_ON_FIRST_COMM  variable removed
Merge pull request #243 from nkogteva/mxm_cleanup

MTL MXM cleanup: unnecessary OMPI_MTL_MXM_CONNECT_ON_FIRST_COMM variable removed
Merge pull request #237 from bureddy/master

oshmem: rename global variables with prefix
mpirun.1in: more updates about binding/etc.

Follow on to 91e9686 and f9d620e.
mpirun.1in: whitespace cleanup

Whitespace cleanup only; no content changes.
MPI_Ibarrier.3in: add missing man page

Add MPI_Ibarrier.3in to reference MPI_Barrier.3, and update
MPI_Barrier.3in to include bindings for MPI_Ibarrier.  Slightly update
the text to be inclusive of the non-blocking case.

Fixes #242.
btl/vader: improved single-copy support

This commit makes the folowing changes:

 - Add support for the knem single-copy mechanism. Initially vader will only
   support the synchronous copy mode. Asynchronous copy support may be added
   int the future.

 - Improve Linux cross memory attach (CMA) when using restrictive ptrace
   settings. This will allow Open MPI to use CMA without modifying the system
   settings to support ptrace attach (see /etc/sysctl.d/10-ptrace.conf).

 - Allow runtime selection of the single copy mechanism. The default behavior
   is to use the best available. The priority list of single-copy mehanisms is
   as follows: xpmem, cma, and knem.

 - Allow disabling support for kernel-assisted single copy.

 - Some tuning and bug fixes.
btl/vader: report an error when a segment cannot be attached
btl/vader: silence warning

correctly check HAVE_SYS_PRCTL_H