Fix SF #1345263, colorsys tests, bug in frange

Fix a typo that caused step to be ignored.

Will backport.
diff --git a/Misc/ACKS b/Misc/ACKS
index b95902a..72ed346 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -271,6 +271,7 @@
 Albert Hofkamp
 Jonathan Hogg
 Gerrit Holl
+Rune Holm
 Philip Homburg
 Naofumi Honda
 Jeffrey Honig