Short version: when the HNP launches VPID 0 on the same node as
itself, the STDIN IOF endpoint will have both a pub and a sub on it.
We need to ensure to only forward incoming messages ''once'' (not
twice, as was happening). A lengthy comment in the code explains in
more detail.
This commit was SVN r18873.
The following Trac tickets were found above:
Ticket 1135 --> https://svn.open-mpi.org/trac/ompi/ticket/1135