improve python packaging

[TomasTomecek]

• [ ] prettier description on PyPI
• [x] add classifiers #46 (thanks @hroncok!)
• [x] automatically push to PyPI when released
• [ ] test release:
  • [ ] from docker hub
  • [ ] from PyPI
• [x] provide wheels

[Tinche]

This is a pure Python project, right? Providing wheels in addition to sdists would be cool. (http://pythonwheels.com/)

[TomasTomecek]

@Tinche no idea how to do those, adding to OP; thank you