Challenges and counter challenges are not more fair by making sure the first bot
being asked for a challenge is the bot next in line according to the bots
position. This way for every challenge-able action our counter action the first
bot is different and not, as before, the first bot in this game.

New rust engine

The engine has been re-implemented from scratch in rust which now comes with a lot more guarantees and types.
A lot of bugs have also been fixed and a large test-suite ensures bugs stay out.