Better BibTeX parsing

Hey David!

sorry about the delay.  got sidetracked by my qualifying exam.  anyways, I've updated the .bib parser:

I'm using this repo for converting .bib files to JSON:
https://github.com/mayanklahiri/bib2json
(it is added as a git submodule, I think you have to run a few extra commands to get the files: http://git-scm.com/book/en/Git-Tools-Submodules)

It deals with a variety of .bib files and overall seems less brittle.  I also added a function in serviette.js that converts the JSON array to the literal array that your D3 code uses.

I've tried it with a few different .bib files and haven't had problems (yet)

cheers,
Niru