grafx - Extensible Java Graphics Package Code

Adding a class-level comment to NightmareModeAction.

Adapting TestGameLogic to new "add layers from bottom" framework.

Adding WooHooSND.java.

Starting to add the better framework for adding layers to bottom of pit at
certain time intervals.

Adding AddLayersFromBottomAlgorithm.

Adding suspend()/resume() to NightmareModeAction.

Adding support for block drop speedup in NightmareModeAction.

Making use of new technique to do gradual system drop block speedups.

Changing level 46 a little bit.

Making first strides at integrating system drop block speedups into
SimpleGameLogic.