Added README.md

Major rearrangement, moved all gameplay data to `data.lisp'

Worked on items and biomes

Changed project name to Naledi ya Africa

Implemented feature creation and drawing (still buggy).

Changed item structs to a CLOS class hierarchy.

Added player.lisp and the inventory handling functions.

Changed some item definitions and other small changes.

Refactored to use the new-* macros

Started on items.lisp