Created base Item class.

This includes some generic variables which will be expanded as the idea of an item is expanded in the game.
Added items list to location.

The map class now loads items from the Map json and saves them in the items list variable in the Locaiton class.
Display a list of purchasable items to the user.

This adds a ListMenu, which is a generic menu that can be used to display a list of objects and returns the actual object that the user selects. This is different than other menus, which return the option the user selected (like 'm' for move).

The 'buy items' menu option should only show when there are items at a location.
Implement the item_buy command.

There are checks in place to make sure the item exists and the player has enough money, then the exchange is made.

I also modified the Player class to show the items in its inventory.

This closes #57.
Added effects list to item.

The effects are defined in the map and loaded in the Map class. This commit does not actually apply these effects, only stores them in the item object.
Added debug string to Item.

This will allow for a string showing exactly what an Item instance contains, which will be useful for debugging.
Implemented item_use command in Game class.

This puts in all of the actions to get to the point of using the item, but the Player class still needs a definition for use_item.
Implement Player.use_item method.
Implemented attributes dictionary and reworked Player.use_item().

This actually fixes use_item(), and the attributes dictionary should be more expandable rather than adding a new variable for each attribute. I didn't move any existing variables to the attributes dictionary yet.
Cleanup.

Removed a debug message.
Added BuyMenu to show the prices for each item you want to buy.

I couldn't find a way to use the ListMenu but to show the prices next to the item, since the string representation of Item is used elsewhere, so I didn't want the price to show up when you went to use the item. This seems to be the best option for now, although it could certainly stand to be redone if we find a better way.
Removed a line I used for debugging (which is not useful to keep).
Merge branch 'master' into add_goods

Conflicts:
	game.py