Switch/nrt - Dynamically load libnrt.so from within the plugin as needed.

This eliminates the need for libnrt.so on the head node.
Expanded BGQ allocation test, needs more work
Update META for v2.5.2 tag
BLUEGENE - Fix in reservation logic that could cause abort.
Merge branch 'slurm-2.5'

Conflicts:
	META
	contribs/arrayrun/Makefile.in
	src/plugins/priority/multifactor2/Makefile.in
Update META for v2.6.0-pre2
Remove "-" from release, use "0pre1" rather than "0-pre1"

rpmbuild is generating an error otherwise:
error: line 99: Illegal char '-' in: Release: 0-pre1
Modify slurm.spec for _optional_ acct_gather_energy plugins

The acct_gather_energy_ipmi.so and acct_gather_energy_rapl.so
files are conditionally built