To allow plays using different user accounts in the same playbook to function,…

To allow plays using different user accounts in the same playbook to function, clear the setup cache
between plays.

lib/ansible/playbook/__init__.py

@@ -81,7 +81,7 @@ class PlayBook(object):
         """
 
         self.SETUP_CACHE = {}
- 
+
         if playbook is None or callbacks is None or runner_callbacks is None or stats is None:
             raise Exception('missing required arguments')
 
@@ -122,6 +122,7 @@ class PlayBook(object):
         # loop through all patterns and run them
         self.callbacks.on_start()
         for play_ds in self.playbook:
+            self.SETUP_CACHE = {}
             self._run_play(Play(self,play_ds))
 
         # summarize the results