Decorator/Overpainter Update

I've updated the decorator to handle most LAF backgrounds. You can now modify the background on just about anything that relies on a parent to paint its background.

The selection marquee is also no longer clipped to its parent component.



Now you might say "I can just paint on my glass pane" and you'd be right except that:
* Your glass pane eats all user input events once it's visible unless you explicitly redirect them
* You glass pane doesn't know anything about what's under it
* It always paints *above* everything else

The AbstractComponentDecorator is a bit more flexible in that you can target all or part of a specific component or a specific area of your window.