Edited the texture-finding code for 1.6

Now correctly avoids globbing problems. Removed a bit of irrelevant code
for old style minecraft.jar. Tweaked error messages for resource packs
instead of texture files.

overviewer_core/world.py

@@ -16,7 +16,6 @@
 import functools
 import os
 import os.path
-from glob import glob
 import logging
 import hashlib
 import time