title: How to invert KML so that area outside of polygon is highlighted
body: <p>I have a KML File which is a polygon that overlays the boundaries of a city. Currently my polygon is shaded gray. I would like to invert it, so the rest of the world is greyed out, </p>
  
  <p>Here is a link to the kml, it should take you to Google maps. <a href="https://docs.google.com/a/edmonton.ca/file/d/0ByG2QfEsXsJ6d01tdlFLS1lObms/edit" rel="nofollow">City of Edmonton</a></p>
  
  <p>I'm not really sure if this is something I need to change in my KML, or can be accomplished with the Google Maps API.</p>