fixed bug while checking role from server when authenticating

ccnode/ccnode.py

@@ -37,7 +37,7 @@ class CCNode(object):
                 logging.warning('Unknown error while authenticating: %s' % err)
             return False
         else:
-            if role is not 'hypervisor':
+            if role != 'hypervisor':
                 logging.warning('Bad role affected by server: %s' % role)
                 return False
             else: