/** function Browser(): get b=browser name
 *  returns: ie-xplorer, mo-zilla, op-era o vacío
 *	@author: NGS */
function Browser(){
	var b='';
	var BN=navigator.appName.substring(0,2);
	if(BN=="Mi") b="ie";
	else if(BN=="Ne") b="mo";
		 else if(BN=="Op") b="op";
		 	  else{b="";}
	return b;
}