this PR moves https://github.com/panter/docker-ci-kubernetes-deploy into this repo
idealy, we would write the just-built image as a tag into the gitlab-ci includes. But that would require a build step for the yaml files themself (e.g. replace a variable with the current tag). But Projects then could no longer import the sources directly, instead they would need to include the generated files. Thats of course possible, but might be a breaking change and/or tricky to do
Since the docker-build step uses a docker-in-docker base image, i added a custom version of this as well as we can now refactor ensureDockerFile scripts more easily