add readme

Author: strangiato

openshift-custom-metrics-autoscaler/README.md

@@ -0,0 +1,32 @@
+# OpenShift Custom Metrics Autoscaler
+
+Install OpenShift Custom Metrics Autoscaler.
+
+Do not use the `base` directory directly, as you will need to patch the `channel` based on the version of OpenShift you are using, or the version of the operator you want to use.
+
+The current *overlays* available are for the following channels:
+
+* [stable](operator/overlays/stable)
+
+## Usage
+
+If you have cloned the `gitops-catalog` repository, you can install Red Hat OpenShift GitOps based on the overlay of your choice by running from the root (`gitops-catalog`) directory.
+
+```
+oc apply -k openshift-custom-metrics-autoscaler/operator/overlays/<channel>
+```
+
+Or, without cloning:
+
+```
+oc apply -k https://github.com/redhat-cop/gitops-catalog/openshift-custom-metrics-autoscaler/operator/overlays/<channel>
+```
+
+As part of a different overlay in your own GitOps repo:
+
+```
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+resources:
+  - https://github.com/redhat-cop/gitops-catalog/openshift-custom-metrics-autoscaler/operator/overlays/<channel>?ref=main
+```