Better installation guides

[ArthurSens]

If we want to offer our own observability stack to potential Gitpod self-hosted users, we need to come up with simple installation strategies, alongside proper documentation.

• Using autogenerated YAML manifests #6
• Modifying generated YAML #7
• Setting up ArgoCD apps #8

[meysholdt]

We should focus on internal customers first and get back to this once there is demand.