title: Galleria using full size images instead of thumbnails
body: <p>When I inspect the element, it indicates galleria is using full size image instead of thumbnail.</p>
  
  <p>Example from Galleria documentation is <a href="http://galleria.io/docs/getting_started/quick_start/" rel="nofollow">http://galleria.io/docs/getting_started/quick_start/</a></p>
  
  <pre><code>&lt;div class="galleria"&gt;
      &lt;a href="/img/large1.jpg"&gt;&lt;img src="/img/thumb1.jpg" data-title="My title" data-description="My description"&gt;&lt;/a&gt;
      &lt;a href="/img/large2.jpg"&gt;&lt;img src="/img/thumb2.jpg" data-title="Another title" data-description="My &lt;em&gt;HTML&lt;/em&gt; description"&gt;&lt;/a&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>My code is </p>
  
  <pre><code>&lt;div class="galleria"&gt;
     &lt;a href="http://upload.wikimedia.org/wikipedia/commons/thumb/2/2f/3D_Schildersdoek.JPG/812px-3D_Schildersdoek.JPG"&gt;
     &lt;img src="http://upload.wikimedia.org/wikipedia/commons/thumb/2/2f/3D_Schildersdoek.JPG/220px-3D_Schildersdoek.JPG" alt=""/&gt;&lt;/a&gt;
     &lt;a href="http://upload.wikimedia.org/wikipedia/commons/thumb/0/02/Bitwa_pod_Grunwaldem_Muzeum_Narodowe_05.JPG/800px-Bitwa_pod_Grunwaldem_Muzeum_Narodowe_05.JPG"&gt;
     &lt;img src="http://upload.wikimedia.org/wikipedia/commons/thumb/0/02/Bitwa_pod_Grunwaldem_Muzeum_Narodowe_05.JPG/300px-Bitwa_pod_Grunwaldem_Muzeum_Narodowe_05.JPG" alt=""/&gt;&lt;/a&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>The link to jsfiddle for demo is <a href="http://jsfiddle.net/zain_aligent/EAVtM/4/" rel="nofollow">http://jsfiddle.net/zain_aligent/EAVtM/4/</a></p>
  
  <p>How can I make galleria use thumbnail images instead of full size images?</p>