- Introduced the concept of tournament systems: a system is a
combination of pairing and a scoring system.
- Tournaments now store "events" in addition to the pairings. Events are
an extensible meta-information mechanism.
- Factored out current hardcoded tournament logic into the "Arena"
system. Arena is the default system.
- Added a "Swiss" system for FIDE-like tournaments. Pairing logic is
based on the FIDE-sanctionned Burstein system.
- The Swiss system pairs players as soon as all games in the previous
round are completed. Players get paired regardless of whether they are
present in the lobby.