wizard mode level teleport (trunk only)

Responding with '?' to the "what level?" prompt when using ^V in
wizard mode brings up a menu of special level destinations that lets you
move across dungeon branches.  But getting in and out of Fort Ludios
didn't work, and jumping to the endgame forced you to arrive on the Plane
of Earth.  Now Fort Ludios will not be selectable in the menu until after
the portal ordinarily used to reach it has been created (so you'll need a
level between Bigroom and Medusa with a vault on it to be created before
you can bypass the magic portal and jump directly to the Fort), and you
can go directly to any of the elemental planes, including Astral, without
stopping at Earth first (the Wizard will be there to greet you, whichever
level you pick).  Also, this limits the menu to endgame entries once you
are in the endgame.  (Previously, picking a non-endgame level would yield
"you can't get there from here"; you can still get that, if you really
want to see it for some reason, by giving a destination level number
outside the range of -1 to -5 instead of using the menu.)

     I hadn't realized that this feature has been around since 3.4.2 until
I couldn't find any new feature entry for in the current fixes file....

doc/fixes35.0

@@ -128,6 +128,7 @@ prevent scroll of charging that has already disappeared from showing in the
 	picklist of things to charge
 doors break instead of absorbing the blast of a broken wand of striking
 avoid "Something's in the way" message with unidentified wand of locking
+better handling for Fort Ludios and endgame in wizard mode's `^V ?' menu
 
 
 Platform- and/or Interface-Specific Fixes