- danielr - use on instead of click to capture dynamically added navigation.

There may be a use case where people would like playlist navigation on the controlbar like so

 $(".fp-controls", root).children().eq(0).after(
                $("<div/>").addClass("fp-prev"),
                $("<div/>").addClass("fp-next")
        );

If this happens after the playlist plugin is added it will not capture the clicks unless on is used. I am providing a feature for this because there is no such thing and I suppose others would need this too. I have something similar for the markers plugin but its for seeking to marker cuepoints. 

I will have to duplicate the code for now. 

Please review thanks.