odls/alps: make sure PMI env. variables set up

Add call to orte_odls_alps_get_rdma_creds in the
local proc launch step to obtain the Cray Rdma
credentials from the apshepherd, and to set
the PMI env. variables expected by uGNI BTL, etc.
ess/pmi: remove daemon code from rte_init/fini

The daemon specific code in the ess/pmi was there
to help out the Cray systems when it was thought
that the cray pmi library had to be used by the
orted's.  The odls/alps component removes the need
for this orted specific code in the ess/pmi component.