title: preg_replace problem
body: <p>I'd like to match and extract variables from: <code>{{variable:int}}</code></p>
  
  <ul>
  <li><strong>variable</strong> would be anything a-z</li>
  <li><strong>:</strong> is a separator</li>
  <li><strong>int</strong> would be an integer 0-9</li>
  </ul>
  
  <p>Curretly i have: <code>preg_replace('!\{\{(\S+)\}\}!', "$1", $string)</code>
  which does only half the job, i still have to split by <code>:</code>.</p>
  
  <p>Thank you!</p>