Shields are armor

Shields are now armor instead of a SpecialItem.
Drop action changed

The drop action is now entirely handled in Map.py.  I plan to change the store and equip actions in the same way.
Room actions are in Map.py

I have now moved every part of drop, store, and equip into Map.py and out of Lib.py.
Combat is handled entirely in Map.py

All of the decisions and results of attacking are handled directly in the Room class in Map.py.  The player may also chose between using to attack or use a special item.  I also started tinkering with special items so that they will work properly with the new setup.