[DGD] Best method to make a wilderness map

[Petter Nyström]

Sorry, I botched my last bullet. It should've read:

 - When a room B would have to be loaded because an object is being
moved there from another room A (e.g. when a player walks around), if
room A has no data that is worth preserving except for the object that
is moving out of it, then instead of loading a new object for room
>>>B<<<, we let room A become room B. This saves us from creating a
lot of new rooms when a player spams across an otherwise deserted
landscape.