title: flickity asNavFor not working
body: <p>this really drives me nuts - everything looks nice and works fine but the click events on the thumbnails don't do anything - anyway to debug this and figure out what's going on - hope somebody has an idea how to fix this - thanks - this is my code: </p>
  
  <pre><code>     var galleryEl = $( '.flickity-gallery[data-id=' + id + ']' );
       var galleryNavEl = $( '.flickity-gallery-nav[data-id=' + id + ']' );
      // Main gallery
      $( galleryEl ).flickity({
          autoPlay:       false,
          //imagesLoaded: true,
          //lazyLoad:     2,
          pageDots:       false
      });
  
      // Thumbnail nav
      $( galleryNavEl ).flickity({
          asNavFor:           '.flickity-gallery-6666',
          cellAlign:          'center',
          contain:            true,
          pageDots:           false,
          wrapAround:         true
      });
  </code></pre>