Edit content for enabling EKS clusters

doc/user/project/clusters/add_remove_clusters.md

@@ -34,7 +34,7 @@ namespace.
 
 This service account will be:
 
-- Added to the installed Helm Tiller
+- Added to the installed Helm Tiller.
 - Used by Helm to install and run [GitLab managed applications](index.md#installing-applications).
 
 Helm will also create additional service accounts and other resources for each
@@ -111,6 +111,11 @@ If you don't want to use GitLab Runner in privileged mode, either:
 
 ## Add new cluster
 
+New clusters can be added using GitLab for:
+
+- Google Kubernetes Engine.
+- Amazon Elastic Kubernetes Service.
+
 ### GKE cluster
 
 GitLab supports:
@@ -206,43 +211,30 @@ GitLab supports:
 Before creating your first cluster on Amazon EKS with GitLab's integration,
 make sure the following requirements are met:
 
-- Enable the `create_eks_clusters` feature flag for your GitLab instance.
+- Self-managed GitLab instances have the `create_eks_clusters` feature flag enabled.
 - An [Amazon Web Services](https://aws.amazon.com/) account is set up and you are able to log in.
 - You have permissions to manage IAM resources.
 
-#### Enable the `create_eks_clusters` feature flag **(CORE ONLY)**
-
-NOTE: **Note:**
-If you are running a self-managed instance, EKS cluster creation will not be available
-unless the feature flag `create_eks_clusters` is enabled. This can be done from the Rails console
-by instance administrators.
-
-Use these commands to start the Rails console:
+##### Enable the `create_eks_clusters` feature flag **(CORE ONLY)**
 
-```sh
-# Omnibus GitLab
-gitlab-rails console
+Self-managed instances must have the feature flag `create_eks_clusters` enabled to create
+EKS clusters. To enable EKS cluster creation, ask a GitLab administrator with Rails console access
+to run the following command:
 
-# Installation from source
-cd /home/git/gitlab
-sudo -u git -H bin/rails console RAILS_ENV=production
-```
-
-Then run the following command to enable the feature flag:
-
-```
+```ruby
 Feature.enable(:create_eks_clusters)
 ```
 
-You can also enable the feature flag only for specific projects with:
+To have it enabled for a specific project only, ask a GitLab administrator to run the following
+command using a Rails console:
 
-```
+```ruby
 Feature.enable(:create_eks_clusters, Project.find_by_full_path('my_group/my_project'))
 ```
 
-Run the following command to disable the feature flag:
+To have this feature disabled, ask a GitLab administrator to run the following command:
 
-```
+```ruby
 Feature.disable(:create_eks_clusters)
 ```