Wall display

Hello,

I added for my intended use of this project a wall display (like jenkins') - a display which can show a maximum of useful information even far from the screen.

The idea is to allow a quick preview of a maximum of PR statuses, clearly visible on a screen from afar, and by the entire team.
So this puts mainly the focus on pull requests' numbers, creator and status, with additional information being the project name and labels. Ideally, it'd be cool to be able to configure what information is displayed, but that's another feature.

In order to keep the current look while adding this one, I implemented it with a client-side config switch - to either display the Github Team Reviewer in "list" or "wall display" mode.

I don't know if this is something you'd like for the project, but I thought I'd try sending a pull request before thinking of switching on my fork :)