TTT WebGame can configure a new PvP game

One player should be able initiate the creation of a new game
Another player should be able to join it

There should be support for match-making either in-band or out-of-band:
 - in-band could be 
   - joining whoever is waiting
   - waiting room of online players
 - out-of-band could be ttt.html showing an invite url that could be sent to another player via IM/email or whatever