Neural network in browser and Extreme mode

The main update this version is a real neural network running right in your browser. The AI got noticeably smarter: it sees positions several moves ahead, knows when to bluff with transfers and when to go all in.

For brave souls we added a new level — Extreme. AI on this difficulty thinks half a minute per move and barely makes mistakes. Beat it once and you can be proud of yourself.

We also polished the online mode: rematches, watching other players, public profiles, push notifications when it is your turn. Playing with friends got much more convenient.