Error in the return of command server show, create

The raw output in the command 'openstack server create'(also in show) is
used in display table directily. the item like
os-extended-volumes:volumes_attached and security_groups needs to convert.

the worry output:
  os-extended-volumes:volumes_attached | [{u'id': u'c3525de9-1cbf-4ac8-8b7a-ca295c46633b'}]
  security_groups                      | [{u'name': u'default'}]

Change-Id: Id9db251c315f989e1dc5b1b6231ab328014213e3

Author: jiahui.qiang

openstackclient/compute/v2/server.py

@@ -144,6 +144,20 @@ def _prep_server_detail(compute_client, server):
     except Exception:
         info['flavor'] = flavor_id
 
+    if 'os-extended-volumes:volumes_attached' in info:
+        info.update(
+            {
+                'volumes_attached': utils.format_list_of_dicts(
+                    info.pop('os-extended-volumes:volumes_attached'))
+            }
+        )
+    if 'security_groups' in info:
+        info.update(
+            {
+                'security_groups': utils.format_list_of_dicts(
+                    info.pop('security_groups'))
+            }
+        )
     # NOTE(dtroyer): novaclient splits these into separate entries...
     # Format addresses in a useful way
     info['addresses'] = _format_servers_list_networks(server.networks)