Refactoring the default theme (for great justice)

So the current state of the default theme is terrible. The CSS is a mess, the HTML is a mess, and it was all hacked together when I was just trying to get a MVP running.

Things are different now. We have the technology to make this a lot better, so that's what this PR is set out to do. Here's what I'm planning:

1. [ ] Rewrite all of the default theme templates using [960.gs](http://960.gs).
2. [ ] Redo all of the CSS in SASS, so it's remotely reasonable to work with/maintain.
4. [ ] Make the original theme easier to use/overall less jank as fuck.
3. [ ] Make the site responsive, so it doesn't look like donkey shit on phones and tablets.

So far I've started on 1, 2, and 3 (which sort of go together), afterwards I'll make it all look good on mobile via responsive niceness.

:beer: