Reorganize room features

[Syndaryl]

Features list needs to be split or tagged to indicate what kind of feature it is.

Definite "must" categories:

• room structure modifications (alcoves, chasms, balconies)
• items in the room (basin, table, game board). These might be further tagged to indicate ruined items vs items in good repair - to pair up with a state of occupation by people-monsters rather than monster-monsters or Empty.

Rooms need only a limited number of structure features per room regardless of size. Item contents, however, should be at least partly proportional to room area, and possibly room occupation.