#612 [bug 2905] Restore focus to editor when a panel is closed

[Mike Cowperthwaite]

I dug into the ugly guts of the DockingManager and figured out a way to restore focus to the editor when one of the panels (e.g. find results, function list, project panel, PythonScript console) is closed.

Two patches: NP6_6_9_editor_focus_on_closed_panel fixes the problem for all panels.
NP6_6_9_docmap_closure removes the explicit call to getFocus() that was put in place to fix this problem when closing Document Map; with the first patch, that call is no longer needed.