Version 2021.11.23.0

Added MinimumYear and MaximumYear properties to the Holiday base class. This allows defining the year range for which a holiday is valid. The defaults are a minimum year of 1 and a maximum year of 9999.

The AddFixed and AddFloating methods of the HolidayCollection class now return the added instance.

The HolidayCollection class will now only return a holiday date if the instance falls within the valid year range for the holiday definition.

The AddStandardHolidays method of the HolidayCollection class was updated to allow passing in a set of one or more additional holiday instances to add to the standard set. If none are specified, only the standard set is used.

Merged a change from Jorge Giménez to the Recurrence class that fixes a bug that caused incorrect results for a rule with a yearly frequency and only a By Month Day rule.