add initial support for non-blocking read and write operations.
btl_base_select: fix faulty/incorrect show_help message

When no components were able to be found, btl_base_select() was
showing the wrong help message -- one that indicated that a specific
component could not be found.  And it left off a string argument, so
the end of the help message was garbage.

This commit creates a new help message for this case and updates the
show_help call to use the new message.
usnic: avoid a possible race condition

Per #4874, code review revealed a possible race condition in the
module struct and the connectivity agent.  Move the setup of the
connectivity agent listener until the module struct has been fully
setup.
The PMI ess component now gets used for more than direct launch, so only set standalone_operation flag if no daemon uri is available so we aggregate show_help messages
Update git/hg ignore files
Remove unwanted spaces + Test commit
Fix shared memory operations - need to pass the local topology and cpusets of all local peers so we can properly compute relative locality for them. Also need to set default locality to "on node" in case where cpusets are not passed because procs are not bound.
Handle the non-blocking fence case correctly, and ensure we always at least pass back the hostname of the process whose info is being requested so that the ompi_proc_t can correctly initialize it when we are in a non-blocking fence with np < cutoff scenario
Backing out the new Opal Hash table until the legal issues are address by H.P.


Refs #4872
Fix the "unreachable" message so it outputs the correct hostname for the remote proc. Cleanup some of the pmix stuff when running corner cases of errors
Little more cleanup under the abort cases cited by Gilles. All seem to be working now
Fix the quoting algorithm so only rsh command lines get quoted values

cmr=v1.8.2:reviewer=jsquyres
Fix a race condition caused by a bad attribute flag that created an OR instead of an AND condition check
Add missing file
Add vvenkates ID.
oshmem configury: tighten up the pshmem checks

Make the checks for macro weak symbols be equivalent to the checks for
weak symbols.

Also fix up several OSHMEM configure checks:

* fix an errant AC_MSG_REQUEST
* don't check for profiling ability during configure options checks.
  Instead, defer it to later, when we have weak symbol check results.
* don't directly call _FOO macros from the top level
* make setting up OSHMEM profiling similar to MPI profiling: create
  OSHMEM_SETUP_PROFILING macro
* cache the results of checking for macro weak symbols (for parity
  with the weak symbol check -- although we should really
  revisit/audit the whole cache-checking scheme throughout all m4
  code; it may well be inconsistently used)
* add some more [] m4 quoting, even in the original C weak symbols test
* style: fix some whitespace errors

Refs #4868
ompi_common_dll.c: the topo mtc union offset must be saved

Since the union contains pointers -- not instances -- we need to save
the mtc offset to get to the pointers later.
pmix: fix process name parsing on 32 bits systems

opal_process_name_t is an uint64_t which is not equivalent to
an unsigned long on 32 bits systems.
this is now parsed as an unsigned long long.
oshmem configury: fix a typo

Fix a typo in r32590

Refs #4868
oshmem configury: fix a test

Fix a test in r32590

Refs #4868