Fixes #4381: Move r31037 to v1.8 branch (Add new MPI-3.1 tools interface)

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r31037 [[BR]]
Add new MPI-3.1 tools interface functions.

See https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/377

This ticket adds the following functions to the standard:

 - MPI_T_cvar_get_index, MPI_T_pvar_get_index, and MPI_T_category_get_index

The ticket has passed and the functions are part of MPI-3.1 that will
be released sometime later this year. In Open MPI the functions expose
existing internal functionality so they are low-risk to add to 1.8.0. I
will leave it up to Ralph whether he wants to accept these into 1.8.

cmr=v1.8:reviewer=rhc
Fixes #4887: Move r32658 to v1.8 branch (oshmem: shpalloc returns the errcode)

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r32658 [[BR]]
oshmem: shpalloc returns the errcode as described in OpenSHMEM 1.1 api

cmr=v1.8.3:reviewer=jladd
Fixes #4883: Move r32623 to v1.8 branch (make_dist_tarball: check for a dirty)

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r32623 [[BR]]
make_dist_tarball: check for a dirty source tree

Have the make_dist_tarball script check to ensure that the source tree
is clean before continuing.  This ensures that we don't accidentally
build a distribution tarball with something that is not committed in
the repo.

There is a --dirtyok option to override this check, and if you access
this script via the "make_tarball" link, --dirtyok is added to the
default set of options.

cmr=v1.8.3:reviewer=rhc