Changes in 2008: - Category 4: added 20 siege tanks to each side. - Allow entries to write data during/in-between games into directory ~/game-data and inform programs about the names of the opponent. This way, entries can learn to adapt to specific players. In category 2 and 3 we will still play twin-games (sides switched). To prevent entries from storing otherwise unobtainable information about twin-games - such as the opponent's location, we will play the first half of games and then clear out the data directories before starting the twin-games in the second half. Categories 1 and 4 don't require twin-games.