Fix SF bug #489581: __slots__ leak.
It was easier than I thought, assuming that no other things contribute
to the instance size besides slots -- a pretty good bet. With a test
suite, no less!
diff --git a/Misc/NEWS b/Misc/NEWS
index 58119ea..eabe9b6 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -4,6 +4,9 @@
Type/class unification and new-style classes
+- Fixed a leak: instance variables declared with __slots__ were never
+ deleted!
+
- The "delete attribute" method of descriptor objects is called
__delete__, not __del__. In previous releases, it was mistakenly
called __del__, which created an unfortunate overloading condition