Removed a few stdlib dependencies.  This is the first step for IronPython support, the second one being a new lexer.

--HG--
branch : trunk
diff --git a/jinja2/debug.py b/jinja2/debug.py
index 9209054..f503c21 100644
--- a/jinja2/debug.py
+++ b/jinja2/debug.py
@@ -11,7 +11,7 @@
     :license: BSD.
 """
 import sys
-from types import CodeType
+from jinja2.utils import CodeType
 
 
 def translate_exception(exc_info):