Introduce common resources for docker templates

This enables common resources that the docker templates might need.
The initial resource only is common volumes, and two volumes are
introduced (localtime and hosts).

Change-Id: Ic55af32803f9493a61f9b57aff849bfc6187d992

docker/services/gnocchi-metricd.yaml

@@ -29,6 +29,9 @@ parameters:
 
 resources:
 
+  ContainersCommon:
+    type: ./containers-common.yaml
+
   GnocchiMetricdBase:
     type: ../../puppet/services/gnocchi-metricd.yaml
     properties:
@@ -65,10 +68,13 @@ outputs:
             privileged: false
             restart: always
             volumes:
-              - /var/lib/kolla/config_files/gnocchi-metricd.json:/var/lib/kolla/config_files/config.json:ro
-              - /var/lib/config-data/gnocchi/etc/gnocchi/:/etc/gnocchi/:ro
-              - /etc/hosts:/etc/hosts:ro
-              - /etc/localtime:/etc/localtime:ro
+              yaql:
+                expression: $.data.common.concat($.data.service)
+                data:
+                  common: {get_attr: [ContainersCommon, volumes]}
+                  service:
+                    - /var/lib/kolla/config_files/gnocchi-metricd.json:/var/lib/kolla/config_files/config.json:ro
+                    - /var/lib/config-data/gnocchi/etc/gnocchi/:/etc/gnocchi/:ro
             environment:
               - KOLLA_CONFIG_STRATEGY=COPY_ALWAYS
       upgrade_tasks: