add extra photo credit

Author: antoinepetty

_includes/footer.html

@@ -35,6 +35,7 @@ <h4>&nbsp;</h4>
         <a href="//www.flickr.com/photos/richardpbarlow/">Richard Barlow</a>,
         <a href="//www.flickr.com/photos/howiegoing/">Howard Buck</a>,
         <a href="//www.flickr.com/photos/theorangeone/">Jake Howard</a>,
+        Laurie Kirkcaldy,
         Anton Nikitin,
         Antoine Petty, and
         <a href="http://www.headington.org/">Headington School Oxford</a>.