Hi,
just want to give a comment about the https stuff as i have setup gitlab on some company servers:
In short: The person handling the server (the OP in this case) is responsible for security and for making gitlab work over https.
There are some tutorials on the internet but not that many, as the gitlab guys mainly make money through support.
If the OP needs some assistance, here is a tutorial for https: http://blog.phusion.nl/2012/04/21/tutorial-setting-up-gitlab-on-debian-6/ or he can PM me (installed it on debian + nginx / apache) or just use good’ol google 
Please be aware that the hoster has full control over the data you upload there.
@OP: If your handing gitlab accounts to strangers be sure to keep it as up to date as possible (imho 6.2.3) and have a tight security around the elements gitlab uses because holes an such :>