[Feature] Add a package manager and pyproject.toml

[felixhoffmnn]

Summarize the feature
The current setup with setup.py and all the other settings files is not quite convenient. Additionally, the packages within the requierements.txt are not correctly checked for compatibility. For that, I recommend using Poetry or Pipenv.

Further, I recommend switching most of the configurations to the pyproject.toml (docs).

Example of the feature
Using Poetry, it is possible to easily manage packages using poetry add and poetry install. It is also possible to define different groups like dev or docs so that you can exclude not necessary packages.

Additional context
None

[zaanposni]

I will have to read through the resources you provided to get a more detailed understanding of the available technologies.
My guess is that we can address the other issues you opened first and do this one later on.