Update notification_driver
Update notification_driver

rabbit_notifier was deprecated in Grizzly and
removed in Icehouse. Adjust to the new name.

Change-Id: If043819897c1b3b8c73e95d1e6682da01b8e5597

MisterPup/Ceilometer-Juno-Extension,ityaptin/ceilometer,sileht/aodh,mathslinux/ceilometer,idegtiarov/ceilometer,pczerkas/aodh,MisterPup/Ceilometer-Juno-Extension,sileht/aodh,maestro-hybrid-cloud/ceilometer,froyobin/ceilometer,fabian4/ceilometer,Juniper/ceilometer,m1093782566/openstack_org_ceilometer,eayunstack/ceilometer,Juniper/ceilometer,r-mibu/ceilometer,isyippee/ceilometer,chungg/aodh,fabian4/ceilometer,m1093782566/openstack_org_ceilometer,pkilambi/ceilometer,maestro-hybrid-cloud/ceilometer,cernops/ceilometer,NeCTAR-RC/ceilometer,pkilambi/ceilometer,pczerkas/aodh,isyippee/ceilometer,chungg/aodh,openstack/ceilometer,redhat-openstack/ceilometer,froyobin/ceilometer,cernops/ceilometer,openstack/ceilometer,tanglei528/ceilometer,mathslinux/ceilometer,luogangyi/Ceilometer-oVirt,luogangyi/Ceilometer-oVirt,eayunstack/ceilometer,NeCTAR-RC/ceilometer,openstack/aodh,ityaptin/ceilometer,redhat-openstack/ceilometer,tanglei528/ceilometer,NeCTAR-RC/ceilometer,openstack/aodh,r-mibu/ceilometer,tanglei528/ceilometer,idegtiarov/ceilometer