Enable oslo.cache library

Add heat:server:cache metadata
      cache:
        engine: memcached
        expiration_time: 600
        backend_argument:
          memcached_expire_time:
            value: 660
        members:
        - host: ${_param:cluster_node01_address}
          port: 11211
        - host: ${_param:cluster_node02_address}
          port: 11211
        - host: ${_param:cluster_node01_address}
          port: 11211

Enable oslo.cache in the heat.conf file

Change-Id: I06b5d2dc0e75626f4c1bb71a81f789f52b4d8717
Related-Prod: PROD-26960
diff --git a/metadata/service/server/single.yml b/metadata/service/server/single.yml
index 3cc782e..9f6dca1 100644
--- a/metadata/service/server/single.yml
+++ b/metadata/service/server/single.yml
@@ -69,3 +69,12 @@
         user: openstack
         password: ${_param:rabbitmq_openstack_password}
         virtual_host: '/openstack'
+      cache:
+        engine: memcached
+        expiration_time: 600
+        backend_argument:
+          memcached_expire_time:
+            value: 660
+        members:
+        - host: ${_param:single_address}
+          port: 11211