grafx - Extensible Java Graphics Package Code

Removing 'userpref' directory from net/blockout/production/.

Removing all Tetris-related stuff. I think this is a dumb game, for dumb
people. I find it to be totally bland, boring, and uninteresting. I don't
want to modify my other code just so that it could play this stupid game.

Adding some anal checks & proofreading code in CanvasSplitter. Adjusting one
'while' loop - using 'do ... while' in its place because that is more correct.
Removing TODO comment because the logic is correct, or it seems to be so, after
close examination. The original code was actually fine.

Modifying the formatting in Javadoc comments.

Adding some comments to CanvasSplitter.

In NightmareLevelTest, removing private inner classes 'SidebarUpdatable' and
'NextBlockUpdatable', replacing with 'SubUpdatable'.

In LevelTest, removing classes 'SidebarUpdatable' and 'NextBlockUpdatable',
replaced with class 'SubUpdatable' defined in CanvasSpitter, the parent class.

In ComputerPlayerTest, removing private inner classes 'SidebarUpdatable' and
'NextBlockUpdatable', and using class 'SubUpdatable' instead.

Removing private inner classes 'SidebarUpdatable' and 'NextBlockUpdatable' from
levelPlayback. Using SubUpdatable (defined in CanvasSplitter) instead.

Removing external class SubUpdatable as promised.