gitlab-markup gem
Renamed the gem and related documentation.
Published a pre-release version on rubygems.org: https://rubygems.org/gems/gitlab-markup. Please name a few other maintainers I should link to in rubygems.org to give access to the gem.
Merge this MR if no other feedback is needed here and I will commit to master a non-pre-release version and update the MR in gitlab-rails: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6659