More obvious code structure

[jmarecek]

Hi all,

it would be great to refactor the code to resemble
https://github.com/humancompatible/interconnect
https://github.com/humancompatible/detect
and any other "major" Python package. That is, within the
https://github.com/humancompatible/train,
there would be
/tests with unit tests
/examples with brief, tutorial-style Jupyter notebooks, ideally named 01_intro, 02_feature1, 03_feature2, etc.
/docs with Sphinx or similar setup to generate documentation, exported to readthedocs.io (cf. https://humancompatible-detect.readthedocs.io/en/latest/)

Thank you!
Jakub