Move Themes to Deftheme Format

Updates the theme to use the new emacs-24 `deftheme` format. Also moves
all the colours into lisp variables.

I prefer being able to use the newer config process with `M-x customize-themes` so I have transitioned one of your themes. I would be prepared to transition the other two if you are interested in them. 

![screen shot 2013-06-28 at 21 12 15](https://f.cloud.github.com/assets/1004401/724266/2ada6e52-e02f-11e2-9eb8-eabf06f0d548.png)