List of holidays that are not fixed absolute or relative dates on the Gregorian calendar.

Attributes

• nonFixed (type: String.t, default: nil) - There are 3 types of holidays supported by the datetime subgrammar: 1) NonFixedHolidayEnum: e.g., "easter", "chinese new year". 2) FetchedRelativeDateTime: e.g., "Thanksgiving" => [4th Thursday of November] 3) HolidayByMonthDay: e.g., "xmas" => [December 25] Each holiday of the first type is resolved by a C++ function; the 2nd and 3rd type of holidays are mapped to AbsoluteDateTime and FetchedRelativeDateTime, respectively, in grammar and are not needed to be represented in proto.