[MICA-8684] add unit tests, restructure project into installable package

[UlieS]

This PR improves the test coverage and general project structure.

It introduces the following changes:

1. restructure the code to be contained in a proper python package setup to create pip installable package (could be hosted on PyPI so producers don't need clone the code)
2. adds unit tests as parts of the code are now importable everywhere across the code base
3. fixes python PEP style