Geo: Generate SSH keys for gitlab user
Talking with @dewetblomerus we came to the conclusion that the step in Geo (gitlab-org/gitlab-ee#76) setup we require SSH keys to be generates with ssh-keygen can be automated by Omnibus.
After a quick search I found something we can use: https://supermarket.chef.io/cookbooks/ssh_keygen.
We can generate it by default for all "EE" installation, as there is currently no "special flag" or configuration we change in gitlab.rb to signal it as a "Geo" node.