Bugfixes and restructuring

* Removed `/routes/`, merged code for routing into `/app.js`
* Made the CSS be searched from the root directory in webpages (`layout.jade`)
* Went line by line in app.js and commented the heck out of it so I'd understand it better
* Finally fixed an issue that would cause jQuery not to preventDefault() on some links
* Hacked in some JS that makes the back button work with AJAX calls, probably buggy lol