Fix for private videos throwing js errors. Bumped version to 2.1.1. Tested with jQuery 1.9 and 2.0.

I had a problem with getting a playlist and one of the videos being private which means it was missing a few fields. Added a quick `if(typeof this.app$control == "undefined")` since app:control is only present if a video is private, unavailable, restricted by location, or otherwise failed to upload. Source https://developers.google.com/youtube/2.0/reference#youtube_data_api_tag_app:control

It has also been tested with jQuery 1.9 and 2.0 with no problems.