engine : abstract state-transition logic
engine : abstract state-transition logic

Refactor to abstract the handle_create/check_create_complete
logic, so it can be reused without lots of duplication for
other action transitions

Prompted by review comments from:
https://review.openstack.org/#/c/31982/2/heat/engine/resource.py
related to blueprint: stack-suspend-resume

Change-Id: Idb18913ef6ff700b63d5ec6d340d2353fc2294b7

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