title: Magnific Popup: source title from span
body: <p>I want to take the title for my Magnific images from a hidden caption field inside the anchor tag - NOT from the title. This is because my title contains markup.</p>
  
  <p>HTML </p>
  
  <pre><code>&lt;a href="img/zoom.jpg"&gt;
    &lt;img src="img/small.jpg" alt=""&gt; 
    &lt;span class="hide"&gt;This is a caption with &lt;a href="#"&gt;a link&lt;/a&gt; in it&lt;/span&gt;
  &lt;/a&gt;
  </code></pre>
  
  <p>JS</p>
  
  <pre><code>// initialise the magnific lightbox
      $('.js-lightbox').each(function() {
        $(this).magnificPopup({
          delegate: 'a',
          type: 'image',
          tLoading: 'Loading image #%curr%...',
          gallery: {
            enabled: true,
            navigateByImgClick: true,
            preload: [0,1] // Will preload 0 - before current, and 1 after the current image
          },
          image: {
            titleSrc: function(item) {
              return item.el.text;
            },
            tError: '&lt;a href="%url%"&gt;The image #%curr%&lt;/a&gt; could not be loaded.'
          }
        });
      });
  </code></pre>
  
  <p>So obviously the <code>return item.el.text;</code> isn't working as expected. Thanks.</p>