Working modular structure

It's not the greatest - site still depends on blog. However, this is
handled internally by the fact that index.js imports blog, then site
(and calls app.use() and them in the correct order).

Views are still served out of the top directory.
Update Bootstrap to latest 3.0.0-wip
Revert "Update Bootstrap to latest 3.0.0-wip"

This reverts commit f232c0486de5611ed3ac4e78f94b363e4d63d247.

Updated Bootstrap changed more things than I wanted to spend time
updating, namely almost their entire grid system.