introduces unique collective ids for the checkpoint/restart code and
with this applied it seems to work pretty good. As this patch also
touches non-CR code it would be good if someone could have a look at it.
With this patch applied the code seems to work up to the point where
orterun actually pauses all processes and tries to create the
checkpoints. The checkpoint creation does not work for me as CRS does
not yet include support for checkpoint/restart using CRIU which would be
my next step.