Fix keystone client usage

The client includes /v3 in the URL.

Author: markgoddard

os_capacity/data/users.py

@@ -14,12 +14,12 @@
 
 
 def get_all(identity_client):
-    response = identity_client.get("/v3/users").json()
+    response = identity_client.get("/users").json()
     raw_users = response['users']
     return {u['id']: u['name'] for u in raw_users}
 
 
 def get_all_projects(identity_client):
-    response = identity_client.get("/v3/projects").json()
+    response = identity_client.get("/projects").json()
     raw_projects = response['projects']
     return {u['id']: u['name'] for u in raw_projects}