Disconnect from the server.

def disconnect(self):
        """Disconnect from the server."""
        # here we just request the disconnection
        # later in _handle_eio_disconnect we invoke the disconnect handler
        for n in self.namespaces:
            self._send_packet(packet.Packet(packet.DISCONNECT, namespace=n))
        self._send_packet(packet.Packet(
            packet.DISCONNECT, namespace='/'))
        self.eio.disconnect(abort=True)