Some core package unit tests fail

[sapols]

I recently added the unit-tests.ipynb notebook which runs core package unit tests. Currently, however, only SunPy's tests pass with 100%.

I'm opening issues in the repos of the other packages to help get them all up to 100%. I'll paste links to them here to keep track of the progress:

1. HAPI
2. PlasmaPy
3. pysat
4. PySPEDAS
5. SpacePy

[sapols]

pysat fixed their failures by including missing data files in the packaged tests, and that will make its way into a future pysat release.

SpacePy also fixed their failure by not hardcoding an "UNRELEASED" version. That'll get rolled into a future SpacePy release, at which point I should update the SpacePy test to run test_all.py!