Revert "Revert "GCW Zero: Accept flicking Power as a way to enter the Main Menu.""

This reverts commit cd31117023d05c105637d505c7d4dbcc2cecd9e0.
Revert "Revert "OpenDingux: Update the manual with the new way to enter the menu.""

This reverts commit 5f1c5c9ca0c194ba2581f2f1a906d5039ddb6c66.