nethack -X vs normal game (trunk only)

Reported to the beta-testers list by <Someone> last April:
restoring a normal game save file in explore mode let you keep the file,
then after exploring and quitting without saving, you could restore it
again in normal mode and take advantage of whatever information you'd
gained.  This makes nethack -X (or playmode:explore) defer the switch to
explore mode when used while restoring a normal mode save file.  It now
performs a normal restore (with save file deletion) and then acts as if
the user had given the 'X' command interactively, requiring confirmation
to actually switch into explore mode.

doc/fixes35.0

@@ -188,6 +188,9 @@ can't drop part of a stack of N weapons welded to hero's hand
 pickup still accepts m as command prefix, but now rejects F,g,G,M,numpad 5
 scatter piles of kicked gold rather than move the entire pile at once
 #jump attempt fails if mounted on sleeping steed; jumping spell still works
+if normal game save file is restored via `nethack -X', restore in normal
+	mode--with save file deletion--and require confirmation ala 'X'
+	command to make deferred switch into explore mode
 
 
 Platform- and/or Interface-Specific Fixes