I manually reviewed

    files/gitlab-config-template/gitlab.rb.template
    files/gitlab-cookbooks/gitlab/attributes/default.rb

from omnibus-gitlab 8.4.2+ce.0-3-g68d5ee8 and picked up changes:

- unicorn OOM killer memory limits were raised up (because gitlab is now
  more memory hungry according to talks on gitlab.com)

  https://gitlab.com/gitlab-org/omnibus-gitlab/commit/f8ee4a19

- there is no default limit for nginx client_max_body_size - it just
  goes to gitlab-workhorse as is at any size

  https://gitlab.com/gitlab-org/omnibus-gitlab/commit/78862837

/cc @kazuhiko, @jerome