Removed risk of co-modification from for() loop in
WorldObject.notifyPositionListeners()
Removed superfluous override from TRFutureTask.
Improved thread safety in SpacePartitioningGrid.
Refactored MemoryManager to use TRFutureTask.
Applied synchronizedList wrapper to SpacePartitioningGrid.branchGrids.
Changed class modifier of WorldObject2DVisibleEverywhere to abstract.
Added Backdrop class to BackdropManager to replace pseudo-anonymous
declaration of WorldObject2DVisibleEverywhere and added debug name to
quad model.
More sync fixes.
Bugfix: Conversion from long to int results in rollover and negative dT.
Added stdout notification that mission.get() is complete.
Incremental redesign of ThreadManager.