title: Is there a way of converting an image to HSL using Pillow?
body: <p>Is there a way of converting an image to HSL with Pillow in Python?</p>
  
  <p>Ideally I would like to be able to open a JPEG, convert it to HSL, change the HSL values, convert back to RGB and save.</p>
  
  <p>The only way I can figure is using <code>colorsys.rgb_to_hls</code> on each pixel.</p>