added run-time flags to enable lighting or nighttime rendering

world.py

@@ -92,9 +92,11 @@ class WorldRenderer(object):
     files to update. If it includes a trailing newline, it is stripped, so you
     can pass in file handles just fine.
     """
-    def __init__(self, worlddir, cachedir, chunklist=None):
+    def __init__(self, worlddir, cachedir, chunklist=None, lighting=False, night=False):
         self.worlddir = worlddir
         self.caves = False
+        self.lighting = lighting or night
+        self.night = night
         self.cachedir = cachedir
 
         self.chunklist = chunklist