Contributing Guide

[vagechirkov]

I think an important step to make foster healthy contributions is to create a contributor guide. I believe this is also crucial for maintenance too. We can use one of the templates as a starting point and then adapt it to our case.

Some useful links:

• https://docs.github.com/en/communities/setting-up-your-project-for-healthy-contributions/setting-guidelines-for-repository-contributors
• https://github.com/github/docs/blob/a3c58ba3b3cf01bef44a710ae5d571042c76a777/CONTRIBUTING.md

I can draft a guide if it sounds good to you! @mezdahun