grafx - Extensible Java Graphics Package Code

Fixing Javadoc in AddLayersFromBottomSoonListener.

Improving Javadoc in GenerateBlocks.

Improving Javadoc in ImprovedBlockSource.

Removing class OrigImprovedBlockSource because it is not being used.

Adding limited visibility constructor to BlocksConfig to make the Javadoc
cleaner-looking.

Adding some better Javadoc to Blocks and to BlocksConfig.

Adding slightly better Javadoc to Blocks.

Working on better Javadoc, better comments, and even added some commented out
error checking code. BlockGenerator and GenerateBlocks.

Removing a 'throws' clause which isn't relevant, in Blocks.

More improvements to Javadoc in BlockGenerator.