Tests, bug fixes, and new phase argument

[rwstauner]

Sorry for the large pull request, but i wanted to add tests before changing anything. If you're interested in any of these commits let me know if there's anything you'd like me to do differently.

This adds tests, improves file handling, and makes it possible to run after release instead of after build.

[fayland]

Thanks for the work, it's released.

[rwstauner]

Sweet. Thanks!