A WoWPro:PrintMessage(msg, chattype, ...) function, that we can use to post whatever message from our addon, with customized formats, etc.

I've been meaning to do this for quite some time and just haven't got around to it

Added WoWPro:Print(). It's very basic, currently just uses Ace's print() function and slaps a yellow WoWPro: in front of it. Can be made fancier later if needed.

Woot!