heat tests : FuncUtils use heat_client in create_stack
heat tests : FuncUtils use heat_client in create_stack

Use heat_client (not subprocess) to create the stack,
as this will allow easier testing of the boto_client
library and easier checking of create_stack result

Change-Id: Ic3f710ec2e467bcd2fde1a2451709d444b89aca0
Signed-off-by: Steven Hardy <4d1810d1ff6d7f22d774341c4549c02173d2f2ab@redhat.com>

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