#1578 new subitem: effort-task not updated

[ltdeta]

Normaly selecting a task the "effort-tab" shows the corresponding efforts.

Adding a new subitem to a task, the new "subtask" will be selected, but the "effort-tab"
continue to show the effort entrys from parent.

If you change the selection and focus the new task again, the corresponding "effort-tab" is correctly empty.