heat common : quieten policy logging
heat common : quieten policy logging

Policy logs the currently loaded policy for every request, which is
too noisy even for debug - we already log the file which contains
the policy when we load it, so this is probably sufficient.

fixes bug 1150091

Change-Id: I0891a30793375c7a0a6b2856db4377eecfeaad8e

rickerc/heat_audit,dims/heat,pshchelo/heat,takeshineshiro/heat,rh-s/heat,NeCTAR-RC/heat,steveb/heat,miguelgrinberg/heat,cwolferh/heat-scratch,miguelgrinberg/heat,dragorosson/heat,varunarya10/heat,cryptickp/heat,maestro-hybrid-cloud/heat,jasondunsmore/heat,rdo-management/heat,citrix-openstack-build/heat,rdo-management/heat,jasondunsmore/heat,Triv90/Heat,dragorosson/heat,takeshineshiro/heat,gonzolino/heat,NeCTAR-RC/heat,redhat-openstack/heat,gonzolino/heat,noironetworks/heat,steveb/heat,ntt-sic/heat,openstack/heat,JioCloud/heat,rh-s/heat,varunarya10/heat,noironetworks/heat,cwolferh/heat-scratch,dims/heat,srznew/heat,Triv90/Heat,pshchelo/heat,openstack/heat,JioCloud/heat,pratikmallya/heat,ntt-sic/heat,maestro-hybrid-cloud/heat,Triv90/Heat,redhat-openstack/heat,citrix-openstack-build/heat,cryptickp/heat,srznew/heat,pratikmallya/heat,rickerc/heat_audit