Adds slot machines to the game.

What it says on the tin.
It works with coins and shit.

emagging it is top lyl and shoots the coins at you.

Probabilities and values are currently completely arbitrary, feel free to suggest changes.

This does not place them on the map.
Call and check the return result of ..() is not true.

Then remove set_machine and add_fingerprint, ..() will handle that.