Add Designate integration

This patch adds Designate support

Change-Id: Ic8391196c0d7eefc6f0ff7b6cc6106d499284e22
Related-PROD: PROD-14689
diff --git a/metadata/service/control/single.yml b/metadata/service/control/single.yml
index 149d37a..0f22b88 100644
--- a/metadata/service/control/single.yml
+++ b/metadata/service/control/single.yml
@@ -48,3 +48,12 @@
         user: nova
         password: ${_param:keystone_nova_password}
         tenant: service
+      backend:
+        extension:
+          dns:
+            enabled: False
+            engine: designate
+            protocol: http
+            host: ${_param:single_address}
+            port: 9001
+            url: ${neutron:server:backend:extension:dns:protocol}://${neutron:server:backend:extension:dns:host}:${neutron:server:backend:extension:dns:port}/v2