Refresh settings.jpg

@ronie

This updates settings.jpg in skin.confluence\backgrounds

It makes attempts to make it more xbmc ish and also puts a Gotham touch
on it. This image could be updated on every release by similar idea related art.

Fixed aspect ratio lock on image dimensions.

Image from blog post
http://xbmc.org/xbmc-13-gotham-september-and-october/

Note I tried to PR this to ronie xbmc fork couldnt do it... gitfoo poor.

thx image author...