Clean up the codebase and write docstrings for necessary functions and classes.

[jeafreezy]

Some docstrings insights:

Article - https://www.dataquest.io/blog/documenting-in-python-with-docstrings/

Google docs string - https://github.com/google/styleguide/blob/gh-pages/pyguide.md#38-comments-and-docstrings

@SammyGIS

[jeafreezy]

This will improve the api reference section of the documentation.