Tests

[blahah]

Having even a very simple testing setup would make contributing to the repo a better experience. Perhaps it could start out as a script that runs eXpress for a bunch of different, small input datasets and sanity checks the output?

[adarob]

Yes, that would be nice for sure...I usually test with a few files on my end, but it's nothing very organized. Again, feel free to add it or I'll get to when I have a chance... :)