code: private void readExceptions(Project.Calendars.Calendar calendar, ProjectCalendar bc)
     {
        Project.Calendars.Calendar.Exceptions exceptions = calendar.getExceptions();
        if (exceptions != null)
        {
           for (Project.Calendars.Calendar.Exceptions.Exception exception : exceptions.getException())
           {
              readException(bc, exception);
           }
        }
     }
docs: Reads any exceptions present in the file. This is only used in MSPDI
  file versions saved by Project 2007 and later.
  
  @param calendar XML calendar
  @param bc MPXJ calendar