Fix #295 - Cope with broken texture references in mod/respack models

src/mcedit2/rendering/blockmodels.pyx

@@ -339,9 +339,7 @@ cdef class BlockModels(object):
 
         textureVars = {}
         for k, v in rawTextureVars.iteritems():
-            if v is None:
-                continue
-            while v.startswith("#"):
+            while v is not None and v.startswith("#"):
                 v = rawTextureVars.get(v[1:])
             if v:
                 textureVars[k] = v