LURE: Use the mouse pointer for menus on the Wii

Without this, this game is almost unplayable, since the
scrolling menus respond to the slightest tilt of the
Wiimote, typically scrolling from the top straight to the
bottom.  Using a mouse pointer in the menus is much easier.
Merge pull request #447 from damien-hackadl/master

LURE: Use the mouse pointer for menus on the Wii
VOYEUR: Simplify the use of _vPort
VOYEUR: Make checkForKey() less verbose
FULLPIPE: Some renames in scenes18 and 19
VOYEUR: Hide the mouse cursor when the low battery screen is displayed
VOYEUR: Hide the mouse cursor when the low battery screen is displayed
VOYEUR: Get rid of some magic values