Move all cluster create documentation to new page

- Also fixes links to old locations where neccessary.
- Put redirect in for an old location.

app/views/clusters/clusters/user/_form.html.haml

-- more_info_link = link_to _('More information'), help_page_path('user/project/clusters/index.md',
-  anchor: 'add-existing-kubernetes-cluster'), target: '_blank'
-- rbac_help_link = link_to _('More information'), help_page_path('user/project/clusters/index.md',
-  anchor: 'role-based-access-control-rbac-core-only'), target: '_blank'
+- more_info_link = link_to _('More information'), help_page_path('user/project/clusters/add_remove_cluster.md',
+  anchor: 'add-existing-cluster'), target: '_blank'
+- rbac_help_link = link_to _('More information'), help_page_path('user/project/clusters/add_remove_cluster.md',
+  anchor: 'access-controls'), target: '_blank'
 
 - api_url_help_text = s_('ClusterIntegration|The URL used to access the Kubernetes API.')
 - ca_cert_help_text = s_('ClusterIntegration|The Kubernetes certificate used to authenticate to the cluster.')

app/views/clusters/clusters/user/_header.html.haml

 %h4
   = s_('ClusterIntegration|Enter the details for your Kubernetes cluster')
 %p
-  - link_to_help_page = link_to(s_('ClusterIntegration|documentation'), help_page_path('user/project/clusters/index', anchor: 'add-existing-kubernetes-cluster'), target: '_blank', rel: 'noopener noreferrer')
+  - link_to_help_page = link_to(s_('ClusterIntegration|documentation'), help_page_path('user/project/clusters/add_remove_cluster', anchor: 'add-existing-cluster'), target: '_blank', rel: 'noopener noreferrer')
   = s_('ClusterIntegration|Please enter access information for your Kubernetes cluster. If you need help, you can read our %{link_to_help_page} on Kubernetes').html_safe % { link_to_help_page: link_to_help_page }

doc/README.md

@@ -305,7 +305,7 @@ The following documentation relates to the DevOps **Configure** stage:
 | Configure Topics                                                                                                                   | Description                                                               |
 |:-----------------------------------------------------------------------------------------------------------------------------------|:--------------------------------------------------------------------------|
 | [Auto DevOps](topics/autodevops/index.md)                                                                                          | Automatically employ a complete DevOps lifecycle.                         |
-| [Create Kubernetes clusters on GKE](user/project/clusters/index.md#add-new-gke-cluster) | Use Google Kubernetes Engine and GitLab.                                  |
+| [Create Kubernetes clusters on GKE](user/project/clusters/add_remove_clusters.md#add-new-gke-cluster)                              | Use Google Kubernetes Engine and GitLab.                                  |
 | [Executable Runbooks](user/project/clusters/runbooks/index.md)                                                                     | Documented procedures that explain how to carry out particular processes. |
 | [GitLab ChatOps](ci/chatops/README.md)                                                                                             | Interact with CI/CD jobs through chat services.                           |
 | [Installing Applications](user/project/clusters/index.md#installing-applications)                                                  | Deploy Helm, Ingress, and Prometheus on Kubernetes.                       |

doc/api/group_clusters.md

@@ -232,7 +232,7 @@ Parameters:
 
 NOTE: **Note:**
 `name`, `api_url`, `ca_cert` and `token` can only be updated if the cluster was added
-through the ["Add existing Kubernetes cluster"](../user/project/clusters/index.md#add-existing-kubernetes-cluster) option or
+through the ["Add existing Kubernetes cluster"](../user/project/clusters/add_remove_clusters.md#add-existing-cluster) option or
 through the ["Add existing cluster to group"](#add-existing-cluster-to-group) endpoint.
 
 Example request:

doc/api/project_clusters.md

 # Project clusters API
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/merge_requests/23922)
-in GitLab 11.7.
+> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/merge_requests/23922) in GitLab 11.7.
 
 NOTE: **Note:**
 User will need at least maintainer access to use these endpoints.
@@ -283,7 +282,7 @@ Parameters:
 
 NOTE: **Note:**
 `name`, `api_url`, `ca_cert` and `token` can only be updated if the cluster was added
-through the ["Add existing Kubernetes cluster"](../user/project/clusters/index.md#add-existing-kubernetes-cluster) option or
+through the ["Add existing Kubernetes cluster"](../user/project/clusters/add_remove_clusters.md#add-existing-cluster) option or
 through the ["Add existing cluster to project"](#add-existing-cluster-to-project) endpoint.
 
 Example request:

doc/user/clusters/applications.md

@@ -7,7 +7,7 @@ These applications are needed for [Review Apps](../../ci/review_apps/index.md)
 and [deployments](../../ci/environments.md) when using [Auto DevOps](../../topics/autodevops/index.md).
 
 You can install them after you
-[create a cluster](../project/clusters/index.md#adding-and-removing-clusters).
+[create a cluster](../project/clusters/add_remove_clusters.md).
 
 ## Installing applications
 
@@ -244,7 +244,7 @@ server to use the external IP address for that domain. For any
 application created and installed, they will be accessible as
 `<program_name>.<kubernetes_namespace>.<domain_name>`. This will require
 your Kubernetes cluster to have [RBAC
-enabled](../project/clusters/index.md#rbac-cluster-resources).
+enabled](../project/clusters/add_remove_clusters.md#rbac-cluster-resources).
 
 NOTE: **Note:**
 The [`knative/knative`](https://storage.googleapis.com/triggermesh-charts)

doc/user/clusters/management_project.md

@@ -20,7 +20,7 @@ This can be useful for:
 ## Permissions
 
 Only the management project will receive `cluster-admin` privileges. All
-other projects will continue to receive [namespace scoped `edit` level privileges](../project/clusters/index.md#rbac-cluster-resources).
+other projects will continue to receive [namespace scoped `edit` level privileges](../project/clusters/add_remove_clusters.md#rbac-cluster-resources).
 
 Management projects are restricted to the following:
 

doc/user/group/clusters/index.md

@@ -58,7 +58,7 @@ differentiate the new cluster from the rest.
 
 You can choose to allow GitLab to manage your cluster for you. If your cluster is
 managed by GitLab, resources for your projects will be automatically created. See the
-[Access controls](../../project/clusters/index.md#access-controls) section for details on which resources will
+[Access controls](../../project/clusters/add_remove_clusters.md#access-controls) section for details on which resources will
 be created.
 
 If you choose to manage your own cluster, project-specific resources will not be created
@@ -147,7 +147,7 @@ are deployed to the Kubernetes cluster, see the documentation for
 
 For important information about securely configuring GitLab Runners, see
 [Security of
-Runners](../../project/clusters/index.md#security-of-gitlab-runners)
+Runners](../../project/clusters/add_remove_clusters.md#security-of-gitlab-runners)
 documentation for project-level clusters.
 
 <!-- ## Troubleshooting

doc/user/project/clusters/runbooks/index.md

@@ -35,7 +35,7 @@ for an overview of how this is accomplished in GitLab!**
 To create an executable runbook, you will need:
 
 1. **Kubernetes** - A Kubernetes cluster is required to deploy the rest of the applications.
-    The simplest way to get started is to add a cluster using [GitLab's GKE integration](../index.md#add-new-gke-cluster).
+    The simplest way to get started is to add a cluster using [GitLab's GKE integration](../add_remove_clusters.md#add-new-gke-cluster).
 1. **Helm Tiller** - Helm is a package manager for Kubernetes and is required to install
     all the other applications. It is installed in its own pod inside the cluster which
     can run the Helm CLI in a safe environment.
@@ -60,7 +60,7 @@ the components outlined above and the preloaded demo runbook.
 
 ### 1. Add a Kubernetes cluster
 
-Follow the steps outlined in [Add new GKE cluster](../index.md#add-new-gke-cluster)
+Follow the steps outlined in [Add new GKE cluster](../add_remove_clusters.md#add-new-gke-cluster)
 to add a Kubernetes cluster to your project.
 
 ### 2. Install Helm Tiller, Ingress, and JupyterHub

doc/user/project/clusters/serverless/index.md

@@ -13,14 +13,16 @@ GitLab supports several ways deploy Serverless applications in both Kubernetes E
 
 Currently we support:
 
-- [Knative](#knative): Build Knative applications with Knative and gitlabktl on GKE
-- [AWS Lambda](aws.md): Create serverless applications via the Serverless Framework and GitLab CI
+- [Knative](#knative): Build Knative applications with Knative and gitlabktl on GKE.
+- [AWS Lambda](aws.md): Create serverless applications via the Serverless Framework and GitLab CI.
 
 ## Knative
 
 Run serverless workloads on Kubernetes using [Knative](https://cloud.google.com/knative/).
 
-Knative extends Kubernetes to provide a set of middleware components that are useful to build modern, source-centric, container-based applications. Knative brings some significant benefits out of the box through its main components:
+Knative extends Kubernetes to provide a set of middleware components that are useful to build
+modern, source-centric, container-based applications. Knative brings some significant benefits out
+of the box through its main components:
 
 - [Serving](https://github.com/knative/serving): Request-driven compute that can scale to zero.
 - [Eventing](https://github.com/knative/eventing): Management and delivery of events.
@@ -39,7 +41,7 @@ To run Knative on GitLab, you will need:
    - If you are planning on deploying a serverless application, clone the sample [Knative Ruby App](https://gitlab.com/knative-examples/knative-ruby-app) to get started.
 
 1. **Kubernetes Cluster:** An RBAC-enabled Kubernetes cluster is required to deploy Knative.
-   The simplest way to get started is to add a cluster using [GitLab's GKE integration](../index.md#add-new-gke-cluster).
+   The simplest way to get started is to add a cluster using [GitLab's GKE integration](../add_remove_clusters.md#add-new-gke-cluster).
    The set of minimum recommended cluster specifications to run Knative is 3 nodes, 6 vCPUs, and 22.50 GB memory.
 1. **Helm Tiller:** Helm is a package manager for Kubernetes and is required to install
    Knative.
@@ -68,7 +70,7 @@ To run Knative on GitLab, you will need:
 NOTE: **Note:**
 The minimum recommended cluster size to run Knative is 3-nodes, 6 vCPUs, and 22.50 GB memory. **RBAC must be enabled.**
 
-1. [Add a Kubernetes cluster](../index.md) and [install Helm](../index.md#installing-applications).
+1. [Add a Kubernetes cluster](../add_remove_clusters.md) and [install Helm](../index.md#installing-applications).
 1. Once Helm has been successfully installed, scroll down to the Knative app section. Enter the domain to be used with
    your application/functions (e.g. `example.com`) and click **Install**.
 
@@ -108,7 +110,7 @@ You must do the following:
 
 1. Follow the steps to
    [add an existing Kubernetes
-   cluster](../index.md#add-existing-kubernetes-cluster).
+   cluster](../add_remove_clusters.md#add-existing-cluster).
 
 1. Ensure GitLab can manage Knative:
    - For a non-GitLab managed cluster, ensure that the service account for the token

doc/user/project/integrations/prometheus.md

@@ -117,7 +117,7 @@ You can view the performance dashboard for an environment by [clicking on the mo
 
 Custom metrics can be monitored by adding them on the monitoring dashboard page. Once saved, they will be displayed on the environment performance dashboard provided that either:
 
-- A [connected Kubernetes cluster](../clusters/index.md#adding-and-removing-clusters) with the environment scope of `*` is used and [Prometheus installed on the cluster](#enabling-prometheus-integration), or
+- A [connected Kubernetes cluster](../clusters/add_remove_clusters.md) with the environment scope of `*` is used and [Prometheus installed on the cluster](#enabling-prometheus-integration)
 - Prometheus is [manually configured](#manual-configuration-of-prometheus).
 
 ![Add New Metric](img/prometheus_add_metric.png)