#adjust tweaks (trunk only)

#adjust tweaks (trunk only)

     Allow '#' as a destination slot if you've given '#' as the source
and there aren't any available inventory letters, making it possible to
use doorganize()'s feature of merging compatible items into one slot even
when that slot is #.  ('#' won't work as a destination when the source is
from a regular letter.  If the player wants to swap something in letter
slot x with whatever is in the # slot, he'll have to use # -> x rather
than x -> #.)

     Also, a post-3.4.3 change made it possible to produce an inventory
that used duplicate letters.  Giving a count while specifying the source
slot splits the source object.  But the extra '?' choice added to show
inventory letters in use didn't undo the split if player hit ESC to quit
early instead of specifying a destination slot.

     Lastly, don't prompt forever if the user doesn't give a valid
destination letter; give up after 5 attempts.