If images are loaded dinamically, image sizing does not work

[tiagofassoni]

Hey!

First of all, thanks for the nice work. We used it in production, works great.

We used it in a situation it wasn't originally designed for, when images are loaded dinamically.

The function does have an implicit trust on all images being loaded for it to work, so I solved it by adding this code to the beforeAfter function:

    $('.ba-slider > img:first').on('load', function() {
      var width_first_image = $('.ba-slider > img:first').width() + 'px';
      cur.find('.resize img').css('width', width_first_image);
    });

I can make the pull request if you wish - just wanted to discuss and validate the solution first.