docs: def __stopOpenThread(self):
          """stop OpenThread stack
  
          Returns:
              True: successful to stop OpenThread stack and thread interface down
              False: fail to stop OpenThread stack
          """
          print 'call stopOpenThread'
          try:
              if self.__sendCommand('thread stop')[0] == 'Done':
                  return self.__sendCommand('ifconfig down')[0] == 'Done'
              else:
                  return False
          except Exception, e:
              ModuleHelper.WriteIntoDebugLogger("stopOpenThread() Error: " + str(e))