Use listen instead of chained notifiers

From Ansible 2.2 onwards, listen can be used for
handlers instead of chaining notifiers. The
handlers are then executed in the sequence
present in the handler file.

Change-Id: Ibe45c76826f9d9830e1315417f336c2d7e23150c

handlers/main.yml

@@ -13,13 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-- name: Restart cinder services
-  command: "/bin/true"
-  notify:
-    - Stop services
-    - Copy new policy file into place
-    - Start services
-
 - name: Stop services
   service:
     name: "{{ item.service_name }}"
@@ -31,6 +24,7 @@
   until: _stop | success
   retries: 5
   delay: 2
+  listen: Restart cinder services
 
 # Note (odyssey4me):
 # The policy.json file is currently read continually by the services
@@ -48,6 +42,7 @@
     group: "{{ cinder_system_group_name }}"
     mode: "0640"
     remote_src: yes
+  listen: Restart cinder services
 
 - name: Start services
   service:
@@ -60,6 +55,7 @@
   until: _start | success
   retries: 5
   delay: 2
+  listen: Restart cinder services
 
 - name: Ensure tgt service restarted
   service: