update default_log_levels set by ceilometer
update default_log_levels set by ceilometer

the current log levels are pretty old. update the current list to
extend current default default_log_level defined in oslo-incubator
and adding in stevedore and keystoneclient levels

Change-Id: I239645ef641613a994a48f20c0238e76dc9660f2
Partial-Bug: #1294789

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