argument: use_stderr_pipe.
(Spawn.__init__): New optional argument: use_stderr_pipe.  Set the
	stderr attribute to an Expectable object that represents the
	stderr output from the subprocess it it is true.  Get rid of
	the __pty attribute, and renamed __child to __child_pid.
(Spawn.send): Use self.fileno() instead of self.__pty.
(Spawn.close): Ditto.  Close the stderr pipe if present.
(spawn2): New function.  A possibly easier API if you want to
	have the stderr output in a separate Expectable.

(Tcp): New class.
(Tcp.__init__): New method.
(Tcp.send): New method.
(Tcp.close): New method.

(Serial): New class.
(Serial.__init__): New method.
(Serial._read): New method.
(Serial.send): New method.
(Serial.close): New method.

(Controller): New name for class controller.  All references updated.

(expect): Documentation added.

(expect_before): Ditto.

	are now set when a match or eof occurs.  Document controller.

"match".

(controller.__init__): New argument: timeout_raises_exception.
(controller.loop): Handle the timeout_raises_exception attribute.
(controller.re): Set the consumed attribute of the expectable.
(controller.eof): Ditto.  Set the match attribute to None, not to
	the consumed string.

classes.  Document expectable.  Let the user class automatically
restore tty settings via atexit.

(expectable.close): New method.

(_saved_mode): New variable.
(_save): New function.  Arrange to call _restore via the atexit module.
(_restore): New function.
(user.__init__): Default to not modifying the termios setting.
	Call _save before changing them.
(user.close): Use _restore to restore the settings.

Don't block when data might be available in the buffer.

(__all__): New constant.
(RAW): New constant.
(CBREAK): New constant.
(COOKED): New constant.
(user): New class.
(user.__init__): New method.
(user.send): New method.
(user.close): New method.

	previous run through the loop.  It may have left parseable
	data in a buffer.

callback functions) to exit the loop.