It does something, but things I don't like:
* it churns for 15 seconds webpacking everything. Do we really need to get
webpack involved here?
* I don't think there's any way to control which tests get run and which don't.
Other things I'd want to fix up include:
* Make it run on jsdom or phantomjs instead of Chrome
* figure out how to configure babel without a .babelrc
