Paul bingo branch

Mostly self-contained changes here except in one place.

I added a simplified event handler and a global broadcaster. I'm not sure if everyone would need this but I've found it to be a useful pattern. I can shift this to be bingo specific if it is not thought to be useful. 

The specific change is in the "Added event broadcaster" change.

Sorry this is embedded in a large pull - I still haven't optimized my git workflow but I think I know how to do this more cleanly in future!

The other changes make bingo finally playable (well if you turn off auto-pick and set the speed to low!)