title: Surf missing in opencv 2.4 for python
body: <p>I'm trying to instantiate a SURF object in python using OpenCV as described <a href="http://docs.opencv.org/modules/nonfree/doc/feature_detection.html#surf">here</a> but this happens:</p>
  
  <pre><code>&gt;&gt;&gt; import cv2
  &gt;&gt;&gt; cv2.__version__
  '2.4.0'
  &gt;&gt;&gt; cv2.SURF()
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
  AttributeError: 'module' object has no attribute 'SURF'
  </code></pre>
  
  <p>Does anyone know why this happens or if SURF is missing from the Python version of OpenCV?</p>