Add Underscore Throttle to updateToolbar and provided option
Pulled in the throttle tool by @VictorBjelkholm as per pull #75

Tested, it doesn't appear to throw any disasters along with all the other changes and the timeout seems to be effective,

Merge branch 'throttle' of github.com:VictorBjelkholm/bootstrap-wysiwyg

Conflicts:
	bootstrap-wysiwyg.js