code: public final List<DayOpeningHours> normalize() {
          final List<HourRanges> ranges = hourRanges.normalize();
          final List<DayOpeningHours> list = new ArrayList<>();
          list.add(new DayOpeningHours(dayOfTheWeek, ranges.get(0)));
          if (ranges.size() > 1) {
              list.add(new DayOpeningHours(dayOfTheWeek.next(), ranges.get(1)));
          }
          return list;
      }
docs: Returns a normalized version of the hour ranges. A day may contain hours that belong logically to the next day.<br>
  An example is 'FRI 18:00-03:00' which means from Friday 6pm to Saturday 3am.<br>
  This example would return then two entries: 'FRI 18:00-24:00' + 'SAT 00:00-03:00'.<br>
  
  @return One or two days.