code: public static Characters allBut(final char... chars)
      {
          final int length = chars.length;
          if (length == 0)
              return ALL;
          final char[] array = Arrays.copyOf(chars, length);
          Arrays.sort(array);
          return new Characters(true, array);
      }
docs: Creates a new Characters instance containing all characters minus the given ones.
  
  @param chars the chars to NOT include
  @return a new Characters object