title: Get UTC from another timezone with Carbon
body: <p>How do I get the UTC date with <a href="https://github.com/briannesbitt/Carbon">Carbon</a> if I use another timezone?</p>
  
  <pre><code>$timestamp = '2014-02-06 16:34:00';
  Carbon::createFromFormat('Y-m-d H:i:s', $timestamp)-&gt;timezone('Europe/Stockholm');
  </code></pre>
  
  <p>I create with a <code>Europe/Stockholm</code> timezone. How do I get the UTC date from that (2014-02-06 15:34)?</p>