[1.5.x] Fixed a remote code execution vulnerabilty in URL reversing.

Thanks Benjamin Bach for the report and initial patch.

This is a security fix; disclosure to follow shortly.

Backport of 8b93b31487 from master

tests/regressiontests/urlpatterns_reverse/nonimported_module.py

@@ -0,0 +1,3 @@
+def view(request):
+    """Stub view"""
+    pass