This is just a script that performs the tasks that are listed at https://github.com/gitlabhq/gitlab-recipes/tree/master/install/centos.
You will need to do a global find and replace on the variables listed at the top of the script. Yes it is hacky but it was easiest way to deal with the escapes.
If you are looking to run this on a virtualbox instance you can use the Vagrant file to build it.
Default login is User: admin@local.host Password: 5iveL!fe