ImageGrabber tools menu swapped between 'Main menubar' and 'Tools' menu without restarting Firefox.

In the Main Menubar, the IHG Tools menu is placed BEFORE the HelpMenu.
As in french, the Help menu label is a single question mark, it's better
to let the help menu at the end of the main menubar.

Signed-off-by: Rookie <Thierry@pb>