Allow job artifacts to be rendered inside of gitlab

Description

Currently if you open a job artifact .html it shows:

The source could not be displayed because it is stored as a job artifact. You can download it instead.

Proposal

The idea is allow to see html artifacts inside gitlab without having to download it and open it locally.

Overview

This will help to see what failed in a UI tests faster, since you need to see pictures normally to see what happened if the test failed, I need to open that html with the results.

Use cases

In my case I use Spoon to run android UI tests and it creates an html with the results, they are not printed in terminal since I need to see device pictures if something goes wrong.