code: public Iterable<Location> redo(Location start) throws ClosedJournalException, CompactedDataFileException, IOException {
          return new Redo(start);
      }
docs: Return an iterable to replay the journal by going through all records
  locations starting from the given one.
  
  @param start
  @return
  @throws IOException
  @throws CompactedDataFileException
  @throws ClosedJournalException