Split users_client from keystone client v2.

Removes users client from identity client v2 into an own one.

Partially implements blueprint consistent-service-method-names

Change-Id: I2473fc29c68c763d02fe2d6ce59266e0eb84816d
diff --git a/tempest/stress/cleanup.py b/tempest/stress/cleanup.py
index 5c25e32..00f760a 100644
--- a/tempest/stress/cleanup.py
+++ b/tempest/stress/cleanup.py
@@ -69,11 +69,11 @@
         except Exception:
             pass
 
-    users = admin_manager.identity_client.list_users()['users']
+    users = admin_manager.users_client.list_users()['users']
     LOG.info("Cleanup::remove %s users" % len(users))
     for user in users:
         if user['name'].startswith("stress_user"):
-            admin_manager.identity_client.delete_user(user['id'])
+            admin_manager.users_client.delete_user(user['id'])
     tenants = admin_manager.tenants_client.list_tenants()['tenants']
     LOG.info("Cleanup::remove %s tenants" % len(tenants))
     for tenant in tenants: