fix test_py3kwarns
The fact that this was failing and went unnoticed so long seems like a good argument for being able to enable and disble py3kwarnings through Python.
diff --git a/Lib/plat-mac/appletrunner.py b/Lib/plat-mac/appletrunner.py
index b47fa42..a2373aa 100755
--- a/Lib/plat-mac/appletrunner.py
+++ b/Lib/plat-mac/appletrunner.py
@@ -4,7 +4,7 @@
# we are not running in a framework build.
from warnings import warnpy3k
-warnpy3k("In 3.x, appletrunner is removed.")
+warnpy3k("In 3.x, appletrunner is removed.", stacklevel=2)
import os
import sys