add after_shutdown hook

python/src/deltachat/account.py

@@ -522,6 +522,7 @@ class Account(object):
             deltachat.clear_context_callback(self._dc_context)
             del self._dc_context
             atexit.unregister(self.shutdown)
+            self._pm.hook.after_shutdown()
 
     def set_location(self, latitude=0.0, longitude=0.0, accuracy=0.0):
         """set a new location. It effects all chats where we currently