Docs: deprecates articles index
See the general Documentation guidelines http://docs.gitlab.com/ce/development/doc_styleguide.html
What does this MR do?
- Last MR for https://gitlab.com/gitlab-org/gitlab-ce/issues/41138
- Deprecates https://docs.gitlab.com/ee/articles/
- Moves remaining articles from list to their topic-related docs
Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/41138
EE-version: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/4093
Edited by Marcia Ramos