glusterfs.spec.in: add psmisc to -server subpackage

apparently some minimalist installs omit psmisc
needed for the killall in various %pre and %post scriptlets

smarter logic for restarting glusterd in %post server

Change-Id: I1581d278c2be6a917c20785437ce78c502111d8d
BUG: 1146624
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>
Reviewed-on: http://review.gluster.org/8859
Tested-by: Gluster Build System <jenkins@build.gluster.com>