Modified block mesh generation to have clearer input and output. Instead of being a messy object oriented cludge, it now is a messy cludge with separate parameters.

src/tile.h

@@ -271,6 +271,7 @@ struct TileSpec
 		// Use this so that leaves don't need a separate material
 		//material_type(MATERIAL_ALPHA_SIMPLE),
 		material_flags(
+			//0 // <- DEBUG, Use the one below
 			MATERIAL_FLAG_BACKFACE_CULLING
 		)
 	{