old unused games not getting cleaned up

[barrybecker4]

Sometimes when a user goes to the boards screen, there are more games shown than there should be.

[barrybecker4]

I believe that the reason is that a user may create a game, then leave and configure a different game.
The originally created game should get cleaned up when they leave.

Another possibility is that a user creates a multi-player game, then closes their browser tab. In this case, we could maintain a timer that cleans up the game when it expires.