Reskinned the TODO UI

I'm submitting a TODO bundle layout and style update to clarify the display of tasks. Colors are mapped to checkbox-like boxes. 

Print styles also display the boxes so that tasks can be marked off for those that choose to waste paper.

Here's a preview: http://cl.ly/image/0T3m2z0M0C2L

Thanks for considering it! And thanks for all the work on TextMate!