[Dillo-dev] start on image maps (dw-part)

Hi - again, it went smoother than expected. The design was well thought out and documented by Sebastian in image.hh. Here comes the dw-part of client side image maps. I could need some help to hook this up in html.cc so I can start testing it. Also the linkEmitter stuff in image.cc needs to be looked at by someone who knows how this works :-) Cheers, Johannes