code: @Override public Task addTask()
     {
        ProjectFile parent = getParentFile();
  
        Task task = new Task(parent, this);
  
        m_children.add(task);
  
        parent.getTasks().add(task);
  
        setSummary(true);
  
        return (task);
     }
docs: This method allows nested tasks to be added, with the WBS being
  completed automatically.
  
  @return new task