ChangeLog:
* Fix null deref when receiving some of dalnet's error end-of-who replies.
* Fix panic caused by /on switch_windows during /window hide.
* New functions, $iptolong(), $longtoip() and $isencrypted().
* Add support for Duhnet's +O channel mode.
* Add support for av2.9's +a channel mode.
* Add support for efnext's 010 "use another server" numeric.
* Change remove_window_from_screen to take a 'hide' argument.
Submitted by: Anders Andersson <anders@codefactory.se> (MAINTAINER)