handler.handle_request: don't bother to spawn self.factory, just call it
read_thread_hixie_76: don't use with_timeout(), hixie_76 doesn't support ping anyway.

go(): demonstrate password authenticator

go(): pass echo_server as channel constructor

msg_channel_open(): construct a new channel class & send confirm

send_channel_request_failure(): new method
Remote_Channel.__init__(): probably incorrect attempt to increment channel id