Automate regression testing

[havijw]

Using something like nbval to do automatic regression testing would be a lot faster and more precise than manually running through notebooks and checking the output.

I can look into this and see how easy and appropriate this would be for our purposes.

[EasyArray]

Yes, thanks! Good idea. It compares the output to previous outputs, so we'd just have to update it when we change what outputs look like or do...

[EasyArray]

Also relevant: https://stackoverflow.com/questions/40172281/unit-tests-for-functions-in-a-jupyter-notebook