Switch to setuptools for packaging

Distribute has been [merged](http://pythonhosted.org/setuptools/merge-faq.html) into setuptools and package maintainers are encouraged to switch. In fact, Arch Linux no longer includes packages for python-distribute.

I tested this in Precise, Lucid, Squeeze, and Arch Linux. It seems fine from what I can tell. I had to move the media/ui data files into the package directory to get setuptools to work with them. Let me know if I missed/broke anything.