This is just a placeholder for ExtractPanelToNib’s implementation:
Create a new nib file with file’s owner “PanelController”, a class designed to manage the panel’s view.
Move the panel nib elements from the parent nib to the child nib file.
Connect all UI to the file’s owner as appropriate.
Add a panel instantiation action to the parent nib’s controller.
Disconnect panel instatiation action from the parent nib elements.
Reconnect panel instantiation to the parent’s controller.
Delete parent nib elements.
Implement CreateViewFromNib.