How to Install GitLab on Ubuntu 16.04

One of the alternatives for Github is the Gitlab git repository manager. In this tutorial, we are going to show you how to install GitLab (Community Edition) on Ubuntu 16.04.
Gitlab offers outstanding features like repository branching, merging, file locking and tagging, time tracking and many more, so you can take full advantage of it.
Gitlab has self-hosted and paid version (Enterprise Edition) and self-hosted and free (Community Edition). In this article, we will install the Community Edition by using the ???omnibus??? package offered by official Gitlab.