Stores (action, activity, server, database) #39

Store added. Stores are really just collections of Inventory
Inventory added, representing an inventory listing in a store
StoreActivity added
StoreServer added. Should be good to go
StoreService stub added
ActionType.STORE added
StoreAction added, which will put a Player into a Store
ActionFactory uses ActionType.STORE to create StoreAction
Inventory table added to the database