MNT : updated crosssection2D messenger
MNT : updated crosssection2D messenger

 - works with re-factored underlying class again
 - removed independent signals/slots for setting the color limits

licode/xray-vision,ericdill/xray-vision,sameera2004/xray-vision,giltis/xray-vision,ericdill/xray-vision,sameera2004/xray-vision,giltis/xray-vision,licode/xray-vision