RFC: Add contributor details to package listing

As discussed in #1935 , here is a revised package listing that displays avatars for all contributors in a package, ordered by the number of contributions.  Each image links back to the user's github page. 

Thoughts welcome. I've attached an image of what it looks like. Any changes you might wish? Should I remove the maintainer image (keep only the text link), and show only the contributor images? 

The code will not win any awards for elegance, but it works for now. 

Please dont merge yet.