Improve the structure and index pages of Administrator documentation

Follow up from https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/15724:

  1. Move https://docs.gitlab.com/ee/administration/operations.html to https://docs.gitlab.com/ee/administration/operations/index.html => https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/15852 + https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/3708
  2. Move Contributor Analytics doc into user/group => https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/3712
  3. Index for https://docs.gitlab.com/ee/administration/monitoring/index.html => https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/15942, https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/3785
  4. Index for https://docs.gitlab.com/ee/administration/monitoring/performance/index.html => https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/15942, https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/3785
  5. Create index for CI/CD admin settings administration/ci_cd/index.html (then add all spread docs there)
  6. Create index for project admin settings /administration/projects/index.html (then add all spread docs there)
  7. Create index for repo admin settings /administration/projects/repositories/index.html (then add all spread docs there)
  8. Move https://docs.gitlab.com/ee/university/high-availability/aws/ to doc/administration/high-availability/aws.html (related: https://gitlab.com/gitlab-org/gitlab-ce/issues/41064)
  9. Move https://docs.gitlab.com/ee/public_access/public_access.html to user/projects/
  10. Create index for doc/customization/ and move all the content to doc/administration/customization/ => https://gitlab.com/gitlab-org/gitlab-ce/issues/41063
  11. Move notifications doc to correct location: https://gitlab.com/gitlab-org/gitlab-ce/issues/41066
  12. /administration/ docs and user/admin_area/ are confusing 😕 Shouldn't they be all under https://docs.gitlab.com/ee/administration/?
  13. Check /integrations/ => some of them are admin-only, so need to be moved under /administration/some_path. E.g., oauth2_generic.md, recaptcha.md, saml.md, shibboleth.md, etc. Also, maybe we should find better terms to define "GitLab integrations" (the ones set up by GitLab admins) and "Project services" (integrations set up by regular users)
  14. Reorg Rake tasks docs: https://gitlab.com/gitlab-org/gitlab-ce/issues/41011
  15. Check HA/Consul nodes docs: https://gitlab.com/gitlab-org/gitlab-ee/issues/4311
  16. Check update Configure GitLab using an external PostgreSQL service => https://gitlab.com/gitlab-org/gitlab-ce/issues/41025

UPDATE: From https://gitlab.com/gitlab-org/gitlab-ce/issues/48724:

We have quite some "loose" docs in the admin folder, we could improve its structure by creating a couple new dirs to organize the content properly:

  • CI/CD-related files: doc/administration/ci_cd/
  • Project-related files: doc/administration/projects/
  • Repo-related files: doc/administration/projects/repositories/
  • Maintenance-related files: doc/administration/maintenance/
  • Email-related files: doc/administration/email/

cc/ @axil @JobV

Edited by Mike Lewis