An enum that holds the different type of week number options in the scheduler.
FirstDay - Denotes that the first week of the year starts on the first day of the year and ends before the following designated first day of the week.FirstFourDayWeek - Denotes that the first week of the year is the first week with four or more days before the designated first day of the week.FirstFullWeek - Denotes that the first week of the year begins on the first occurrence of the designated first day of the week on or after the first day of the year.