Places: Added functions for adding and getting places, and for finding places of specific types. Added beds, chairs and chest as places.
NPC: Added places map and action queue.
Moved trading and pricing code to another folder, separate files.
NPC: Added further inventory functionality.
Trading: Added price data structure, which allows for setting prices for items. Also includes some default definitions.
Modified NPCs so random dialogues are chosen on initialization.
Added function to start a dialogue, choosing randomly NPCs dialogues.
Changed NPC code to use new dialogue code