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);
     eventsByTitle.Add(title.ToLower(), newEvent);
     evetsByDate.Add(newEvent); Message.EventAdded();
 }