Added close_endpoint_on_shutdown option on TunnelProtocol

    def __init__(self, *args, **kwargs):

        endpoint = kwargs.pop('endpoint', None)

        autostart = kwargs.pop('autostart', True)

        self._cb_on_shutdown = kwargs.pop('on_shutdown', self.cb_default_on_shutdown)

        self._cb_on_shutdown = kwargs.pop('on_shutdown', None)

        self._close_endpoint_on_shutdown = kwargs.pop('close_endpoint_on_shutdown', True)

        super(TunnelProtocol, self).__init__(*args, **kwargs)

        if endpoint is None:

    def cb_default_on_shutdown(self, tun):

        """ Action to do on the endpoint when the connection is shutdown.

        """

        tun.endpoint.close()

        pass

#

# Public methods:

            except RpcConnectionError:

                pass  # Ignore errors when connection is down.

            # Execute the callback:

            if self._cb_on_shutdown is not None:

                self._cb_on_shutdown(self)

            if self._close_endpoint_on_shutdown:

                self.endpoint.close()

            super(TunnelProtocol, self).shutdown()

    def wait_shutdown(self, timeout=None, sig_timeout=1):