extending verify to check semantics: both options must be set or unset together

HelloKitty.scala

      (dateOpt, oldRankerPairsFileOpt) match {
        case (Some(_),Some(_)) => Console.err.println("You gave both a date and the previous ranker-pairs file.  Good.")
        case (None, None) => // nothin' is nothin' is nothin'
        case _ => sys.error("You have to give an old ranker-pairs file for a date, and vice versa.  Bad.")
      }