Provides basic game logic entities to manage a game where the logic is executed by turns:
Game, GameTurn, GameEvent, Turnable.
Also offers a bucket system to plan future events at a known number of turns in the future:
Bucketable and the services act_next and act_in.
Efficiently support large number of entities with rare or sparse actions, such as a forest with many individual trees growing slowly.
bucketed_game :: bucketed_game
Game framework with an emphasis on efficient event coordination