Use awx-manage register_default_execution_environments

Signed-off-by: Julen Landa Alustiza <jlanda@redhat.com>

README.md

@@ -556,6 +556,30 @@ In a scenario where custom volumes and volume mounts are required to either over
 
 Example configuration for ConfigMap
 
+#### Default execution environments from private registries
+
+In order to register default execution environments from private registries, the Custom Resource needs to know about the pull credentials. Those credentials should be stored as a secret and either specified as `ee_pull_credentials_secret` at the CR spec level, or simply be present on the namespace under the name `<resourcename>-ee-pull-credentials` . Instance initialization will register a `Container registry` type credential on the deployed instance and assign it to the registered default execution environments.
+
+The secret should be formated as follows:
+
+```yaml
+---
+apiVersion: v1
+kind: Secret
+metadata:
+  name: <resourcename>-ee-pull-credentials
+  namespace: <target namespace>
+stringData:
+  url: <registry url. i.e. quay.io>
+  username: <username to connect as>
+  password: <password to connect with>
+  ssl_verify: <Optional attribute. Whether verify ssl connection or not. Accepted values "True" (default), "False" >
+type: Opaque
+```
+
+##### Control plane ee from private registry
+The first default execution environment will be deployed as part of the control plane. In order to use a private image for this you'll need to use `image_pull_secret` to provide a k8s pull secret to access it.
+
 ```yaml
 ---
 apiVersion: v1