Clean up gateway sections in README.md (istio-ecosystem#428)

Consolidate duplicate gateway sections and add a link to the OpenShift example.

docs/README.md

@@ -236,10 +236,6 @@ spec:
 
 Note that the only field that was added is the `spec.version` field. There are a few situations however where the APIs are different and require different approaches to achieve the same outcome.
 
-### Gateways
-
-Sail Operator does not support deploying Gateways using `spec.values.gateways`, only Gateway Injection and Gateway API are currently supported. See the [Gateways](#gateways) section for more information.
-
 ### components field
 
 Sail Operator's Istio resource does not have a `spec.components` field. Instead, you can enable and disable components directly by setting `spec.values.<component>.enabled: true/false`. Other functionality exposed through `spec.components` like the k8s overlays is not currently available.
@@ -254,10 +250,12 @@ The functionality of the istiod-remote chart is exposed through the [RemoteIstio
 
 ## Gateways
 
-The Sail Operator does not manage Gateways. You can deploy a gateway manually either through [gateway-api](https://istio.io/latest/docs/tasks/traffic-management/ingress/gateway-api/) or through [gateway injection](https://istio.io/latest/docs/setup/additional-setup/gateway/#deploying-a-gateway). As you are following the gateway installation instructions, skip the step to install Istio since this is handled by the Sail Operator.
+[Gateways in Istio](https://istio.io/latest/docs/concepts/traffic-management/#gateways) are used to manage inbound and outbound traffic for the mesh. The Sail Operator does not deploy or manage Gateways. You can deploy a gateway either through [gateway-api](https://istio.io/latest/docs/tasks/traffic-management/ingress/gateway-api/) or through [gateway injection](https://istio.io/latest/docs/setup/additional-setup/gateway/#deploying-a-gateway). As you are following the gateway installation instructions, skip the step to install Istio since this is handled by the Sail Operator.
 
 **Note:** The `IstioOperator` / `istioctl` example is separate from the Sail Operator. Setting `spec.components` or `spec.values.gateways` on your Sail Operator `Istio` resource **will not work**.
 
+For examples installing Gateways on OpenShift, see the [Gateways](common/create-and-configure-gateways.md) page.
+
 ## Update Strategy
 
 The Sail Operator supports two update strategies to update the version of the Istio control plane: `InPlace` and `RevisionBased`. The default strategy is `InPlace`.