/*** Get selection id's of categories and or items ***/
function countCheckBoxes (element)
{
    // get all checkboxes
    var checkBoxes = $('.downloadCheckboxes');
    var count = 0;
    
    // count the number checked
    for(var i=0;i < checkBoxes.length; i++){
     // if count > 3 uncheck box and show alert
     if(checkBoxes[i].checked)
      count++;
    }
    
	if(count > 3){
	  element.checked = false;  
	  alert("U kunt maximaal 3 artikelen per keer bestellen");
	}
}