Added holidays viewer

lib/storage/holidays/holidaysSettings.dart

@@ -0,0 +1,14 @@
+import 'package:json_annotation/json_annotation.dart';
+
+part 'holidaysSettings.g.dart';
+
+@JsonSerializable()
+class HolidaysSettings {
+  bool dismissedDisclaimer;
+  bool showPastEvents;
+
+  HolidaysSettings({required this.dismissedDisclaimer, required this.showPastEvents});
+
+  factory HolidaysSettings.fromJson(Map<String, dynamic> json) => _$HolidaysSettingsFromJson(json);
+  Map<String, dynamic> toJson() => _$HolidaysSettingsToJson(this);
+}