#3 Patch for lightbox

[dan moore]

Attached is a patch for issue 1821277: http://sourceforge.net/tracker/index.php?func=detail&aid=1821277&group_id=169692&atid=851374

I couldn't figure out how to attach the patch to that issue, so I put it here.

Basically, this fixes things so the image for the lightbox is pulled relative to the module's base url, rather than the page the gwt is called from.

[dan moore]

patch to Lightbox.java