code: static int compareWithNullHigh(Object a, Object b) {
          return a == null ? (b == null ? 0 : -1) : (b == null ? 1 : ((Comparable) a).compareTo(b));
      }
docs: Compares two objects which are assumed to be Comparable. If one value is
  null, it is treated as being higher. This consistent with all other
  property value comparisons in carbonado.