Open Issues
* teleporters and spinners cannot be removed/enabled
* non wall items are only rendered in the center line of view, 
  requiring architectural measures to prevent the player from noticing too easily
* interaction can only affect one cell    
* The monster might also hit the player when the player choses to retreat (0 and 1 on D8).
* Roll initiative for the first attack (user upper bits of timer?)

Fixed Issues
+ opening doors doesn't consume a key
+ doors open without a key
+ the fountain doesn't work (victory item not given)
