Topic/remove pmi

This set of commits removes the dependency of the orte daemons on Cray PMI.  This is done by
implementing a new ess/alps and odls/alps components for use by the orted's running on Cray XE/XC compute nodes.

The odls/alps component obtains the GNI RDMA credentials from the ALPS apshepherd process and
passes these credentials to the uGNI BTL and other consumers of the GNI API.

The ess/alps component obtains a rank for the daemon using the alps_get_placement_info method.

The pmix base select call within the ess/pmi component is now moved into the query method for that
component.  Code for special casing for the daemon processes in the ess/pmi rte_init/fini methods is
removed as this is no longer needed.

This set of commits also removes the restriction that prior to this, Open MPI on Cray XE/XC would not work except when the --disable-dlopen configure option was selected.

The ORTE_CHECK_ALPS m4 macro is significantly simplified to take advantage of the extensive use of
pkg-config tools for the cray specific CLE 5 system libraries.  On CLE 4 systems, the macro detects whether or not Open MPI is being built on login node of the system, or on an external ESlogin node, and looks for the libalpslli/libalpsutil/apInfo.h in the appropriate directories.

@rhc54 could you please review this, particularly commit hppritcha/ompi@74f5492