Documentation review: Workhorse

Background

Workhorse is a critical component of GitLab application infrastructure, and belongs to groupsource code. It was previously a separate repo, but has now moved onto the main GitLab Rails repo.

At present the documentation consists of README and associated files in the Workhorse folder.

Purpose

Discovery issue to find out what needs doing from a docs perspective, as requested in Slack.

Improve the Workhorse docs and eventually move them into the main documentation, with this page as the landing page.