modified jquery.prettyembed.js to allow multiple instances

Added:

    $(this).attr('id', thisVideoID);

Just after:

    if ( $(this).attr('data-pe-videoid') !== undefined ) { thisVideoID = $(this).attr('data-pe-videoid'); }
			else if ( $(this).attr('href') !== undefined ) { thisVideoID = youtube_parser( $(this).attr('href') ); }
			else { thisVideoID = options.videoID; }
____
Changed:

    $(this)

To:

    $(e.target)

In:

     $('body').on('click', '.pretty-embed', function(e) {
			e.preventDefault();

			clickEventRunner( $(e.target) );
		});

Because it seemed like `this` was working in the wrong context.
____
Changed:

    else if ( options.videoID !== undefined ) { thisVideoID = options.videoID; }

To:

    else if ( obj.attr('id') !== undefined ) { thisVideoID = obj.attr('id'); }

In:

    if ( obj.attr('data-pe-videoid') !== undefined ) { thisVideoID = obj.attr('data-pe-videoid'); }
			else if ( options.videoID !== undefined ) { thisVideoID = options.videoID; }
			else {
				thisVideoID = undefined;
				console.error('PrettyEmbed.js Error:  Misformed or missing video ID.');
			}

To set video id from 'id' attribute that was added earlier.

I **did not** check for other use cases (such as the "HTML5 Driven Application" example).