Added parallax scrolling background
Fix: no parallax scrolling in FF

Fixed problem with parallax background  not working under FF
merge parallax into dev, remove default image #595
update code style to match rest of reveal.js, disable parallax by default #595
move parallax code to separate method #595
update the parallax background when the window resizes #595
use 'url()'-free path when specifying parallax image, refactor so that parallax is applied to background class, remove unused attributes #595
remove extravagant comment
serve remotes js from s3 #611
Focus body when page visibility changes to ensure keyboard shortcuts are usable
Property 'length' is not a variable.
Merge branch 'master' of github.com:hakimel/reveal.js into dev
remove unused head.js in barebones example #616
Merge branch 'focus-body-on-visibility-change' of https://github.com/rexxars/reveal.js into dev
code style
add autoSlideStoppable config value, allows autoSlide to be aborted on user input
shell highlight #642
Merge branch 'patch-1' of https://github.com/webpro/reveal.js into dev
use named link for fragments #621
remove accidentally checked in files