using stl::sets for descriptive adjectives
Merge branch 'feature/items' of https://github.com/tindrum/Zorkey_Park into feature/items

Add clause (with|from) to parser
add "use" and "grab" verbs. Added "clause" data member to Command object.
Trying to implement all Item containers as set<Item*> collections. Lots of objects have a list of Items: Rooms, NPCs, Player (has his backpack), even other Items like Vase can contain other objects.
Halfway done implementing this. Probably should have an ItemCollection class. Probably should have a search path for items (Player -> Room at least, in leu of specifically-named item to search).
items sort of working. Each object that can have items has an ItemContainer.
Rooms now stored in a hash to ease adding items to rooms by room name.
Text display of all items in room now when you enter a room. Will need to put that in "inspect room" or "search room" instead later.