First step - build all needed software. We build:

- Git
- PostgreSQL 9.2
- Redis 2.8
- Nginx

- gitlab-shell
- gitlab-workhorse
- gitlab-ce 8.2 itself

and everything which is needed to build the above programs.

Git is needed because GitLab is a git-hosting service and uses git
underneath. PostgreSQL is used as DB by gitlab and Redis as a cache.

GitLab-shell is a small project to manage ssh access to the service
(we'll disable ssh though) and to perform all "change a repository"
operations.

GitLab-workhorse is a service which offloads long-running or slow
request from main GitLab service.

GitLab-ce is the main Ruby-on-Rails-based web application.

Ruby- and Go- based programs are built in a way similar to:

    - 31a45a94    (helloworld & helloweb: Ruby version), and
    - 24e82414    (helloworld & helloweb: Go version)

Version of all components, except Git, were picked the same, as used by
gitlab omnibus v8.2 .

/cc @kazuhiko, @jerome