Fix an occasional 400 error on functional gate

This error occurs on bay-delete. The cause is that heat sometimes
deleted the routerinterface resource before the deletion of its
associated floatingip resource. This commit adds a dependency to
avoid the incorrect order of deletion.

Change-Id: I099a68e65d70076b94a17103f57a8b09d7aaad88
Closes-Bug: #1504298

magnum/templates/heat-kubernetes/kubecluster.yaml

@@ -291,6 +291,8 @@ resources:
 
   api_pool_floating:
     type: OS::Neutron::FloatingIP
+    depends_on:
+      - extrouter_inside
     properties:
       floating_network: {get_param: external_network}
       port_id: {get_attr: [api_pool, vip, port_id]}

magnum/templates/heat-mesos/mesoscluster.yaml

@@ -222,6 +222,8 @@ resources:
 
   mesos_master_floating:
     type: OS::Neutron::FloatingIP
+    depends_on:
+      - extrouter_inside
     properties:
       floating_network: {get_param: external_network}
       port_id: {get_resource: mesos_master_eth0}