change to sprite images
update Gruntfile
update jericho.css
Merge remote-tracking branch 'marexandre/v2_branch' into gh-pages

* marexandre/v2_branch:
  update jericho.css
  update Gruntfile
  change to sprite images

Conflicts:
	Gruntfile.coffee
	jericho.css
	lib/_alerts.scss
	lib/_forms.scss
	lib/_variables.scss