Add to pypi

[stantond]

So that it can be more easily discovered and then installed with PIP

[avaldebe]

Yes, I'll make sure the next first release ends up on PPI

[avaldebe]

TODO

• [x] close #3
• [x] cose #4
• [x] merge #5
• [x] tag 0.3.0 and create release (trigger zenodo DOI)
• [x] publish test.pypi