PyLint

[nettle]

Describe the task

Introduce pylint for python and potentially bazel code verification

Scope

1. Find an elegant and reliable way to add pylint to the project
2. Define very simple, first iteration of pylint workflow and rules
3. Suggest simple, easy-to-use pylint configuration
4. Plan cleanup and CI integration as next steps

Definition of Done

• Clear for all developers how to use pylint in the project
• Simple requirements are described
• CONTRIBUTING is updated