title: Remove properties from rendered Less CSS
body: <p>There seem to be some patterns in LessCSS (1.7.x) that allow (pre/post)-processing of a CSS render tree. I was wondering if it was possible to use the Visitor (I tried that, but couldn't make it work - or anything else) to remove properties from the CSS output upon rendering.
  E.g. if the output was</p>
  
  <pre><code>a {
   font-size: 12px;
   -some-aribitrary-property: value;
  }
  </code></pre>
  
  <p>I would like to remove <code>-some-arbitrary-property</code> from the CSS output when calling <code>.toCSS</code>.
  I can't seem to find any documentation about this, only references to the upcoming version 2.0 - does anyone know if this is even possible and if yes how to do so, or point me to some example?</p>