Fix errors in fuel_plugin_example_v3

* Set volumes to empty list by default (we use this value in list's
  extend method).
* Use 'role' attribute for post deployment task, since 'groups' is used
  only for main deployment.
* Fix 'cmd' line for post deployment task.

Change-Id: I36212b106f27411edc0ce36cd1827ce14ea5eb72
Signed-off-by: Igor Kalnitsky <igor@kalnitsky.org>

fuel_plugin_builder/fuel_plugin_builder/templates/v3/plugin_data/volumes.yaml.mako

@@ -1,6 +1,7 @@
 volumes_roles_mapping:
+  # Default role mapping
   ${plugin_name}:
-    # Default role mapping
     - {allocate_size: "min", id: "os"}
-volumes:
-  # Set here new volumes for your role
+
+# Set here new volumes for your role
+volumes: []

fuel_plugin_example_v3/deployment_tasks.yaml

@@ -10,16 +10,6 @@
     strategy:
       type: parallel
 
-- id: fuel_plugin_example_v3-post-deployment-sh
-  type: shell
-  groups: [fuel_plugin_example_v3]
-  required_for: [post_deployment_end]
-  requires: [post_deployment_start]
-  parameters:
-    cmd: deploy.sh
-    retries: 3
-    interval: 20
-    timeout: 180
 
 - id: fuel_plugin_example_v3-deployment
   type: puppet
@@ -30,3 +20,15 @@
     puppet_manifest: "deploy.pp"
     puppet_modules: ""
     timeout: 3600
+
+
+- id: fuel_plugin_example_v3-post-deployment-sh
+  type: shell
+  role: [fuel_plugin_example_v3]
+  required_for: [post_deployment_end]
+  requires: [post_deployment_start]
+  parameters:
+    cmd: ./deploy.sh
+    retries: 3
+    interval: 20
+    timeout: 180

fuel_plugin_example_v3/volumes.yaml

@@ -1,5 +1,5 @@
-volumes:
-  # set here new volumes for your role
+# Set here new volumes for your role
+volumes: []
 volumes_roles_mapping:
   fuel_plugin_example_v3:
     # Default role mapping