Add and move CI menu entries
Based on feedback, the link to the .gitlab-ci.yml
reference topic from the global nav is misleading. It indicates a link to comprehensive configuration topics whereas that topic is just one part of it.
That renames that entry and demotes it.
Also adds a quick link to the getting started guide.
Forms part of: https://gitlab.com/gitlab-org/gitlab-ce/issues/58323.
Edited by Evan Read