Tests for ipython notebooks

[babbush]

We've had a few problems with people submitting pull requests that break the demo file. The demo is quite important because it is likely the first thing that new users will read. However, we currently have no method to test whether it runs without errors. Such a test would save us a lot of trouble!

[babbush]

To illustrate the importance of this: I think @idk3 recent changes which moved the UCC code into the circuits folder (which I merged) may have broken the demo. @idk3 can you please fix the demo? I think getting tests for the demo in place should really be a priority.

[idk3]

Yep, I'm on it now.

[idk3]

Fixing the imports was not enough, there's a deeper problem somewhere in the call to energy_objective. I'll continue to look at this.

[babbush]

👍

[idk3]

OK, I have a fix. The problem was pretty subtle and is not related to my changes, though in retrospect I should've thought of it earlier. I'll send a PR soon.

[idk3]

#138

[babbush]

Thanks. @damiansteiger are these tests for the demo ipython notebook (just something to make sure the notebook can run without errors) something you can help us with in the next couple weeks? It is really bad that we keep breaking the demo and I frankly don't really know how to write such tests myself. You had once mentioned to me that it could be done.