- config.ru template is gone - pristine gitlab-ce/config.ru can do the
  job because it obtains unicorn OOM killer setting via environment
  variables.

  https://gitlab.com/gitlab-org/omnibus-gitlab/merge_requests/672

- we put TODO there for configuring trusted proxies (gitlab.yml & nginx)

- we restore our slaposified configuration from config.ru to unicorn.rb