Write introduction to GitOps workflows for KKP CRDs
We mention "GitOps" workflows (mostly interacting with KKP through the Kubernetes API directly) in several places, e.g. our release notes, but we should probably write a comprehensive introduction to how to use it, what limitations it has (in particular with RBAC), and how it can allow you to integrate with popular GitOps tools (without going into too much detail).
Some migration notes from REST API usage would also be interesting.
Currently, we have something here: https://github.com/kubermatic/community-components/blob/master/components/api/README.md
see PR https://github.com/kubermatic/community-components/pull/111
somehow @csengerszabo needs to decide where we want to keep this