title: Horizontally align thumbnails in center
body: <p>Following is the code I'm using in my html with twitter-bootstrap. I am trying to center align the output but the image is left-aligned no matter what I do.</p>
  
  <pre><code>&lt;ul class="thumbnails"&gt; 
     &lt;li class="span5"&gt;
      &lt;a href="#" class="thumbnail"&gt;&lt;img src="img.jpg" /&gt;&lt;/a&gt;
     &lt;/li&gt;
  &lt;/ul&gt;
  </code></pre>
  
  <p>Any simple solution?</p>