Add a release-note theme and document the new config file format too

Signed-off-by: Richard Wall <[email protected]>

Author: wallrj

content/docs/releases/release-notes/release-notes-1.18.md

@@ -9,7 +9,11 @@ cert-manager v1.18 includes:
 
 ## Major Themes
 
-### TODO
+### Copy annotations from Ingress or Gateway to the Certificate
+
+We've added a new configuration option to the cert-manager controller: `--extra-certificate-annotations`, which allows you to specify annotation keys to be copied from an Ingress or Gateway resource to the resulting Certificate object.
+Read [Annotated Ingress resource: Copy annotations to the Certificate](../../usage/ingress.md#copy-annotations-to-the-certificate ), and
+[Annotated Gateway resource: Copy annotations to the Certificate](../../usage/gateway.md#copy-annotations-to-the-certificate), to learn more.
 
 ## Community
 

content/docs/usage/gateway.md

@@ -438,8 +438,30 @@ Certificate resources:
   configure `spec.privateKey.rotationPolicy` field to set the rotation policy of the private key for a Certificate.
   Valid values are `Never` and `Always`. If unset a rotation policy `Never` will be used.
 
-It is possible to copy any specific custom annotation into generated `Certificate` object.
-Like below, custom `Venafi` configuration could be specified. When `cert-manager` is started with `--extra-certificate-annotations=venafi.cert-manager.io/custom-fields`
+## Copy annotations to the Certificate
+
+> ℹ️ This feature was added in cert-manager `v1.18.0`.
+
+It is possible to copy any specific custom annotation into the generated `Certificate` objects.
+For example, to copy the annotation: `venafi.cert-manager.io/custom-fields` from the Gateway to the Certificate,
+you must first redeploy the cert-manager controller with the following extra argument:
+
+```
+--extra-certificate-annotations=venafi.cert-manager.io/custom-fields
+```
+
+Or if you use Helm, supply the following values:
+
+```yaml
+# values.yaml
+config:
+  ingressShimConfig:
+    extraCertificateAnnotations:
+    - venafi.cert-manager.io/custom-fields
+```
+
+Then you can add the annotation to the Gateway resource:
+
 ```yaml
 apiVersion: gateway.networking.k8s.io/v1
 kind: Gateway

content/docs/usage/ingress.md

@@ -177,8 +177,30 @@ trigger Certificate resources to be automatically created:
   configure `spec.privateKey.rotationPolicy` field to set the rotation policy of the private key for a Certificate.
   Valid values are `Never` and `Always`. If unset a rotation policy `Never` will be used.
 
-It is possible to copy any specific custom annotation into generated `Certificate` object.
-Like below, custom `Venafi` configuration could be specified. When `cert-manager` is started with `--extra-certificate-annotations=venafi.cert-manager.io/custom-fields`
+## Copying annotations to the Certificate
+
+> ℹ️ This feature was added in cert-manager `v1.18.0`.
+
+It is possible to copy any specific custom annotation into the generated `Certificate` objects.
+For example, to copy the annotation: `venafi.cert-manager.io/custom-fields` from the Ingress to the Certificate,
+you must first redeploy the cert-manager controller with the following extra argument:
+
+```
+--extra-certificate-annotations=venafi.cert-manager.io/custom-fields
+```
+
+Or if you use Helm, supply the following values:
+
+```yaml
+# values.yaml
+config:
+  ingressShimConfig:
+    extraCertificateAnnotations:
+    - venafi.cert-manager.io/custom-fields
+```
+
+Then you can add the annotation to the Ingress resource:
+
 ```yaml
 apiVersion: networking.k8s.io/v1
 kind: Ingress