public static void PrintEvent(Event eventToPrint)
 {
     if (eventToPrint != null)
     {
         output.Append(eventToPrint + "\n");
     }
 }
        public void AddEvent(DateTime date, string title, string location)
        {
            Event newEvent = new Event(date, title, location);

            this.byTitle.Add(title.ToLower(), newEvent);
            this.byDate.Add(newEvent);

            Messages.EventAdded();
        }