Improve testing

[bcongdon]

Next big push is to get the actual tests working. #3 reduced the dependencies between the app and trackers, so it should be possible to unit test the trackers without having to load / startup the app. (If it isn't, then that's something to do too)

Not sure how much testing is necessary for an external api driven project like this, but something better than running the updateall cli command would be good. 👍