UI overhaul

Completely rewrote most of the templates in HAML and CoffeeScript. Templates now make heavy use of DataTables as well. I think everything is more or less working, but there are a bunch of minor things to clean up, plus there's the image index page left. I started a TODO.txt file in the root folder and dumped a bunch of thoughts in there; please take a look and maybe tackle anything that looks doable in the next few days. I'm not sure how much time if any I'll have to work on this over the weekend, but I'll try to make one more pass before Monday.