* README updated

README

@@ -8,6 +8,7 @@ New bricks:
 * Cactus (plant that grows on sand)
 * Clay (found in sand at sea level, yields 4 lumps of clay)
 * Brick (made from 4 clay bricks, yields 4 clay bricks)
+* Papyrus (plant that grows in shallow water)
 
 New materials:
 * Lump of clay