Parsing finalization

Further updates to the parsing system have been implemented.

-All items and monsters in the original version of the game have been
re-added in this new system.
-Monsters now read from a CFG file like the items.
-CFG files have been annotated to make editing by the end-user more
accessible.
-A new script file, UTILS, has been added although at this time it is
not used. This file will contain utility functions.
-A checkerboard pattern has been placed on the laboratory floors.
-Cosmetic improvements have been made to the in-game menus.