HtwKinect: Add beach image

photo credit: <a href="http://www.flickr.com/photos/msojka/3635666013/">
Martin Sojka .. www.VisualEscap.es</a>
via <a href="http://photopin.com">photopin</a>
<a href="http://creativecommons.org/licenses/by-nc-sa/2.0/">cc</a>
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