grafx - Extensible Java Graphics Package Code

Redo parts of SimpleGameLogic to incorporate recent changes related to cleared
layers events.

Rename waitMillisBetweenStaticEvents to millisWaitBetweenStaticEvents. Add
millisWaitLevelFinished. This will break other code for the time being.

Modifying ScoreGenerator to work with new BlockoutGamestateListener API.

Modifying layerCleared() to pass single layer cleared events. This will break
code. Still working on it. In BlockoutGamestateListener.

Modifying EventEncoder.java to work with the revised ClearedLayersEvent. The
code may still be in a state of flux; even compiling may not work at this
point.

Revising ClearedLayersEvent to add new strategy of animating a sequence of
disappearing layers. This may break some code for the time being. It may not
even compile, not sure. I want to commit now because it's a good stopping
point, after extensive proofreading and analyzing this situation.

Adding level23-game-5.blo.

Adding scripts/launch-impossible-level-test.sh.

Augmenting TODO.txt, explaining how we could do an animated CLEARED_LAYERS
where multiples are being cleared.

In SimpleGameLogic, now waiting for LEVEL_FINISHED and GAME_OVER events to be
processed before invoking m_gamestateListener. This is how other static events
are handled: you wait for the event to be processed before proceeding.