Make a new step by step guide for new users of the template

[janhalen]

Step by Step guide.

Explain how to use the simple GitHub workflow to collaborate on the documentation in a consistent and transparent way

Consider dividing the guide into 2 parts or maybe even 2 seperate documents if that makes it easier to onboard the correct roles. One for the documentation maintainer team, and one for contributors.

[janhalen]

Direct link to affected documents:

https://github.com/OS2offdig/os2-docs-template/blob/25-make-a-new-step-by-step-guide-for-new-users-of-the-template/README.md

[janhalen]

A suggestion is to make a much simpler version of the README... make a "PROJECT_README_TEMPLATE" and some rolespecific guides for maintainers and simple contributors