Remove duplicate entries.

doc/ci/examples/README.md

 # CI Examples
 
-- [Testing PHP](php.md)
+- [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)
-- [The .gitlab-ci.yml file for GitLab itself](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/.gitlab-ci.yml)
-- [Test your PHP applications](examples/php.md)
-- [Test and deploy Ruby applications to Heroku](examples/test-and-deploy-ruby-application-to-heroku.md)
-- [Test and deploy Python applications to Heroku](examples/test-and-deploy-python-application-to-heroku.md)
-- [Test Clojure applications](examples/test-clojure-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.
@@ -17,3 +12,4 @@
 
 - [Blost 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)