(DON'T MERGE) Fixes #286: Softlock inside of "darkness"

[libraun]

• If the player turns on the flashlight (currently just with 'Under' rooms) and the flashlight is off, then it will be lost for the rest of the game, and the player is warned that they'll need to 'find their way out without (a flashlight)';
• If the player drops the flashlight when it is toggled on, the room will be lit, and the player can pick up the flashlight.
• The rooms lose light again once the activated flashlight is picked up

[spacehobo]

See my updates in #286. Also you can just remove the call for review if you want this not to be merged.