Full response for v3 PolicyClient methods

Provide the entire response object for all methods of the v3
PolicyClient

partially implements: blueprint method-return-value-and-move-service-clients-to-lib

Change-Id: I475df3bf3a3c2e36fc982867224f3104be3910af
diff --git a/tempest/services/identity/v3/json/policy_client.py b/tempest/services/identity/v3/json/policy_client.py
index f820598..3231bb0 100644
--- a/tempest/services/identity/v3/json/policy_client.py
+++ b/tempest/services/identity/v3/json/policy_client.py
@@ -31,14 +31,14 @@
         resp, body = self.post('policies', post_body)
         self.expected_success(201, resp.status)
         body = json.loads(body)
-        return service_client.ResponseBody(resp, body['policy'])
+        return service_client.ResponseBody(resp, body)
 
     def list_policies(self):
         """Lists the policies."""
         resp, body = self.get('policies')
         self.expected_success(200, resp.status)
         body = json.loads(body)
-        return service_client.ResponseBodyList(resp, body['policies'])
+        return service_client.ResponseBody(resp, body)
 
     def get_policy(self, policy_id):
         """Lists out the given policy."""
@@ -46,7 +46,7 @@
         resp, body = self.get(url)
         self.expected_success(200, resp.status)
         body = json.loads(body)
-        return service_client.ResponseBody(resp, body['policy'])
+        return service_client.ResponseBody(resp, body)
 
     def update_policy(self, policy_id, **kwargs):
         """Updates a policy."""
@@ -59,7 +59,7 @@
         resp, body = self.patch(url, post_body)
         self.expected_success(200, resp.status)
         body = json.loads(body)
-        return service_client.ResponseBody(resp, body['policy'])
+        return service_client.ResponseBody(resp, body)
 
     def delete_policy(self, policy_id):
         """Deletes the policy."""