Merge branch 'docs-fix-duplicate-sections' into 'master'

Docs: fix duplicate sections (CI docs)

See merge request gitlab-org/gitlab-ee!4090

doc/administration/index.md

@@ -43,13 +43,6 @@ Learn how to install, configure, update, and maintain your GitLab instance.
 - [Welcome message](../customization/welcome_message.md): Add a custom welcome message to the sign-in page.
 - ["New Project" page](../customization/new_project_page.md): Customize the text to be displayed on the page that opens whenever your users create a new project.
 
-#### Customizing GitLab's appearance
-
-- [Header logo](../customization/branded_page_and_email_header.md): Change the logo on all pages and email headers.
-- [Branded login page](../customization/branded_login_page.md): Customize the login page with your own logo, title, and description.
-- [Welcome message](../customization/welcome_message.md): Add a custom welcome message to the sign-in page.
-- ["New Project" page](../customization/new_project_page.md): Customize the text to be displayed on the page that opens whenever your users create a new project.
-
 ### Maintaining GitLab
 
 - [Raketasks](../raketasks/README.md): Perform various tasks for maintenance, backups, automatic webhooks setup, etc.

doc/ci/README.md

@@ -83,15 +83,6 @@ Leverage the power of Docker to run your CI pipelines.
 - [CI services (linked Docker containers)](services/README.md)
 - Article (2016-03-01): [Setting up GitLab Runner For Continuous Integration](https://about.gitlab.com/2016/03/01/gitlab-runner-with-docker/)
 
-## GitLab CI/CD for Docker
-
-Leverage the power of Docker to run your CI pipelines.
-
-- [Use Docker images with GitLab Runner](docker/using_docker_images.md)
-- [Use CI to build Docker images](docker/using_docker_build.md)
-- [CI services (linked Docker containers)](services/README.md)
-- Article (2016-03-01): [Setting up GitLab Runner For Continuous Integration](https://about.gitlab.com/2016/03/01/gitlab-runner-with-docker/)
-
 ## Review Apps
 
 - [Review Apps documentation](review_apps/index.md)
@@ -106,17 +97,6 @@ Leverage the power of Docker to run your CI pipelines.
 
 See the documentation on [GitLab Pages](../user/project/pages/index.md).
 
-## Special configuration (GitLab admin)
-
-As a GitLab administrator, you can change the default behavior of GitLab CI/CD in
-your whole GitLab instance as well as in each project.
-
-- **Project specific:**
-  - [Pipelines settings](../user/project/pipelines/settings.md)
-  - [Learn how to enable or disable GitLab CI](enable_or_disable_ci.md)
-- **Affecting the whole GitLab instance:**
-  - [Continuous Integration admin settings](../user/admin_area/settings/continuous_integration.md)
-
 ## Examples
 
 Check the [GitLab CI/CD examples](examples/README.md) for a collection of tutorials and guides on setting up your CI/CD pipeline for various programming languages, frameworks,
@@ -128,6 +108,18 @@ and operating systems.
 - Article (2016-05-05): [Getting Started with GitLab and Shippable Continuous Integration](https://about.gitlab.com/2016/05/05/getting-started-gitlab-and-shippable/)
 - Article (2016-04-19): [GitLab Partners with DigitalOcean to make Continuous Integration faster, safer, and more affordable](https://about.gitlab.com/2016/04/19/gitlab-partners-with-digitalocean-to-make-continuous-integration-faster-safer-and-more-affordable/)
 
+## Special configuration (GitLab admin)
+
+As a GitLab administrator, you can change the default behavior of GitLab CI/CD in
+your whole GitLab instance as well as in each project.
+
+- [Continuous Integration admin settings](../administration/index.md#continuous-integration-settings)
+- **Project specific:**
+  - [Pipelines settings](../user/project/pipelines/settings.md)
+  - [Learn how to enable or disable GitLab CI](enable_or_disable_ci.md)
+- **Affecting the whole GitLab instance:**
+  - [Continuous Integration admin settings](../user/admin_area/settings/continuous_integration.md)
+
 ## Breaking changes
 
 - [CI variables renaming for GitLab 9.0](variables/README.md#9-0-renaming) Read about the