Sends a stop signal to the loop thread

        :param silent: True/False value that specifies whether or not to raise RuntimeError if the loop is currently not
        running
        :return:

def send_stop_signal(self, silent=False):
        """Sends a stop signal to the loop thread

        :param silent: True/False value that specifies whether or not to raise RuntimeError if the loop is currently not
        running
        :return:
        """
        if self.is_running():
            self._stop_signal = True
        elif not silent:
            raise RuntimeError('Loop is currently not running')