[Call for testers] GitLab

[Torsten Zuehlsdorff]

Hello,

today i updated the patch to bring GitLab to its newest version. Also 
i've added an update guide. If the feedback is still as positive as now 
i will write the outstanding PRs for the dependencies next week, so the 
committers can take care of the port.

If we success in committing before April i can state, that i took me 
less than a year to create the port. :P

Link to PR and patch:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=202468

Greetings,
Torsten