Create release process

[ghost]

I as developer Daniela want to have a structured release process to provide quality assurance for our code base.

Acceptance criteria

• we have a release concept
• the release concept can be implemented in our repos
• at least two-man rule is implemented

Hints

• major.minor.patch

Subtasks

• [ ] Investigate
• [ ] present findings to team

[ghost]

First draft is available at the bottom of our README.md but up for debate.