title: CakePHP caching elements with duration
body: <p>Regarding to <a href="http://book.cakephp.org/2.0/en/views.html#caching-elements" rel="nofollow">cookbook</a> we can cache elements like this:</p>
  
  <pre><code>echo $this-&gt;element('helpbox', array(), array('cache' =&gt; true));
  </code></pre>
  
  <p>Caching with configuration is like this:</p>
  
  <pre><code>echo $this-&gt;element('helpbox', array(),
      array('cache' =&gt; array('config' =&gt; 'view_long') );
  </code></pre>
  
  <p>How can I cache elements without predefined configuration ? How can I cache duration to elements? I tried this, but didn't work:</p>
  
  <pre><code>echo $this-&gt;element('helpbox',  array(),
       array('cache' =&gt; array('time' =&gt; '+30 minutes')));
  </code></pre>