Downgrade the quality of the Hal and Wally AI bots once all humans have been eliminated from the game

[hlhoots]

When playing at conferences, often a player may be eliminated quickly by not understanding the controls, etc, and then the remaining AI bots for Hal and Wally often keep playing for up to 60 seconds.

Would like a simple change such that once all the human players are eliminated from a round that the two AI bots automatically just go in a straight line for the remainder of the time they are alive (ie, we want to eliminate the AI bot players as fast as possible so the game can quickly be restarted for another round).