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

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

smarter logic for restarting glusterd in %post server

Change-Id: I041f22576f25e200ff6a4e2f194e539ba7ed1d42
BUG: 1113543
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>
Reviewed-on: http://review.gluster.org/8871
Reviewed-by: Niels de Vos <ndevos@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Lalatendu Mohanty <lmohanty@redhat.com>