Add ability to configure extensions via local.conf
Add ability to configure extensions via local.conf

Add variables DESIGNATE_ENABLED_EXTENSIONS_V1 and V2
Enable quotas by default

Change-Id: Ieac9885f7571d4864eed109f3c5273e027d7f0d2

grahamhayes/designate,tonyli71/designate,openstack/designate,muraliselva10/designate,kiall/designate-py3,ramsateesh/designate,cneill/designate,grahamhayes/designate,muraliselva10/designate,ionrock/designate,cneill/designate-testing,kiall/designate-py3,kiall/designate-py3,cneill/designate,cneill/designate,cneill/designate,openstack/designate,openstack/designate,cneill/designate-testing,cneill/designate,tonyli71/designate,ramsateesh/designate,ionrock/designate,kiall/designate-py3,grahamhayes/designate,ionrock/designate,cneill/designate-testing,tonyli71/designate,ramsateesh/designate,kiall/designate-py3,muraliselva10/designate