This is a bit of a cleanup of the original codebase and makes it a bit simpler to understand as there isn't much code duplication. I did, however, take out a few features from the original which I didn't need. I will slowly readd them in the future.
Irssi growl script taken from here.
(ON/OFF/TOGGLE) Send a notification on private messages
(ON/OFF/TOGGLE) Send a notification when your name is hilighted
(ON/OFF/TOGGLE) Send a notification when someone on your away list joins or leaves
(ON/OFF/TOGGLE) Send a notification when the topic for a channel changes
Set to the hostname you want to send notifications to
On a Mac network this may be computer.local
The port on the destination computer
The growl password of the destination computer