SF patch #1473132:  Improve docs for tp_clear and tp_traverse,
by Collin Winter.

Bugfix candidate (but I'm not going to bother).
diff --git a/Misc/ACKS b/Misc/ACKS
index 3f1b47c..f1caf97 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -658,6 +658,7 @@
 Frank Willison
 Greg V. Wilson
 Jody Winston
+Collin Winter
 Dik Winter
 Blake Winton
 Jean-Claude Wippler