Fix dead links in the docs (Jun 2016) ## What does this MR do? Fix dead links in the docs found as of Jun 2016. ## Are there points in the code the reviewer needs to double check? n/a ## Why was this MR needed? This MR must improve UX on docs.gitlab.com. ## What are the relevant issue numbers? Closes #19156 ## Does this MR meet the acceptance criteria? - No [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) updated - [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md) - [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides) - [x] Branch has no merge conflicts with `master` (if you do - rebase it please) - [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits) See merge request !4921
Clarify artifact expiry ## What does this MR do? Clarifies documentation about artifact expiry. ## Are there points in the code the reviewer needs to double check? ## Why was this MR needed? ## What are the relevant issue numbers? ## Screenshots (if relevant) See merge request !4831
Document `GIT_STRATEGY` and `GIT_DEPTH` ## What does this MR do? Documents `GIT_STRATEGY` and `GIT_DEPTH`. Also fixes the TOC since the anchors weren't working. ## Are there points in the code the reviewer needs to double check? The TOC and the location of the new entries. ## Why was this MR needed? ## What are the relevant issue numbers? https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/merge_requests/188 ## Screenshots (if relevant)   /cc @axil @ayufan See merge request !4720
* Adds pipelines page to CI docs. * Adds image of pipelines list (although currently missing border that is on other images). * Changes CI to CI/CD in `/doc` and `/doc/ci` * Sorts user documentation in `/doc` Partially fixes #17733. See merge request !4660