mongodb: make count an integer explicitely
mongodb: make count an integer explicitely

This fixes bug #1124350

Change-Id: I389a3f228fd3e1718d242189d9579a3b56852ca1
Signed-off-by: Julien Danjou <5c682c2d1ec4073e277f9ba9f4bdf07e5794dabe@danjou.info>

fabian4/ceilometer,maestro-hybrid-cloud/ceilometer,rickerc/ceilometer_audit,rackerlabs/instrumented-ceilometer,openstack/aodh,tanglei528/ceilometer,froyobin/ceilometer,MisterPup/Ceilometer-Juno-Extension,NeCTAR-RC/ceilometer,cernops/ceilometer,cernops/ceilometer,isyippee/ceilometer,Juniper/ceilometer,mathslinux/ceilometer,NeCTAR-RC/ceilometer,JioCloud/ceilometer,pkilambi/ceilometer,NeCTAR-RC/ceilometer,redhat-openstack/ceilometer,isyippee/ceilometer,eayunstack/ceilometer,shootstar/ctest,citrix-openstack-build/ceilometer,mathslinux/ceilometer,rackerlabs/instrumented-ceilometer,ityaptin/ceilometer,eayunstack/ceilometer,dreamhost/ceilometer,citrix-openstack-build/ceilometer,luogangyi/Ceilometer-oVirt,sileht/aodh,ityaptin/ceilometer,m1093782566/openstack_org_ceilometer,openstack/aodh,idegtiarov/ceilometer,r-mibu/ceilometer,pczerkas/aodh,rackerlabs/instrumented-ceilometer,openstack/ceilometer,luogangyi/Ceilometer-oVirt,citrix-openstack-build/ceilometer,rickerc/ceilometer_audit,shootstar/ctest,sileht/aodh,chungg/aodh,idegtiarov/ceilometer,pczerkas/aodh,JioCloud/ceilometer,rickerc/ceilometer_audit,m1093782566/openstack_org_ceilometer,redhat-openstack/ceilometer,tanglei528/ceilometer,MisterPup/Ceilometer-Juno-Extension,froyobin/ceilometer,pkilambi/ceilometer,dreamhost/ceilometer,JioCloud/ceilometer,r-mibu/ceilometer,Juniper/ceilometer,tanglei528/ceilometer,maestro-hybrid-cloud/ceilometer,openstack/ceilometer,fabian4/ceilometer,chungg/aodh