Chore: Add license and repo to setup.py

[WilliamRoyNelson]

Added some basic documentation to setup.py This adds a link to the GitHub repo so that users on PyPI can easily refer to the source code, as well as including the license.

[asmith26]

This would also be useful for me. In particular I'm using liccheck to automatically check any python packages we use are compatible with our license needs. Thanks

[wandeder]

It will be very useful for me too, because a lot of pipelines which use liccheck falls down without info about license in this package.

[WilliamRoyNelson]

This is also a convenient opportunity to add any additional classifiers. @fchollet if there's any that you'd like me to add prior to merge, let me know!