Merge branch 'zj-update-ci-examples-doc' into 'master'

Minor update on CI docs examples

cc @ayufan @markpundsack 

Commit message: 

> Triggered by gitlab-org/gitlab-ci-yml#1 I've investigated how this is
organized so far and did a minor clean up. In my opinion we should just
keep a list of up to date blog posts in the docs and examples should be
included in gitlab-org/gitlab-ci-yml. This reduces the number of
projects and docs pages one has to look for information.

See merge request !5806

doc/ci/examples/README.md

 # CI Examples
+A collection of `.gitlab-ci.yml` files is maintained at the [GitLab CI Yml project][gitlab-ci-templates].
+If your favorite programming language or framework are missing we would love your help by sending a merge request
+with a `.gitlab-ci.yml`.
+
+Apart from those, here is an collection of tutorials and guides on setting up your CI pipeline:
+
 - [Testing a PHP application](php.md)
 - [Test and deploy a Ruby application to Heroku](test-and-deploy-ruby-application-to-heroku.md)
 - [Test and deploy a Python application to Heroku](test-and-deploy-python-application-to-heroku.md)
 - [Test a Clojure application](test-clojure-application.md)
 - [Test a Scala application](test-scala-application.md)
 - [Using `dpl` as deployment tool](deployment/README.md)
-- Help your favorite programming language and GitLab by sending a merge request
-  with a guide for that language.
-
-## Outside the documentation
-
 - [Blog post about using GitLab CI for iOS projects](https://about.gitlab.com/2016/03/10/setting-up-gitlab-ci-for-ios-projects/)
 - [Repo's with examples for various languages](https://gitlab.com/groups/gitlab-examples)
 - [The .gitlab-ci.yml file for GitLab itself](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/.gitlab-ci.yml)
-- [A collection of useful .gitlab-ci.yml templates](https://gitlab.com/gitlab-org/gitlab-ci-yml)
+
+[gitlab-ci-templates][https://gitlab.com/gitlab-org/gitlab-ci-yml]