code: function getSortComparator(fnCompare) {
  		return function(vValue1, vValue2) {
  			if (vValue1 === vValue2) {
  				return 0;
  			}
  			if (vValue1 === null) {
  				return -1;
  			}
  			if (vValue2 === null) {
  				return 1;
  			}
  			return fnCompare(vValue1, vValue2);
  		};
  	}
docs: Creates a comparator usable for sorting.
  
  The OData comparators return "NaN" for comparisons containing null values. While this is a valid result when used for filtering,
  for sorting the null values need to be put in order, so the comparator must return either -1 or 1 instead, to have null sorted
  at the top in ascending order and on the bottom in descending order.
  
  @private