Merge branch 'master' of github.com:celery/celery

CONTRIBUTORS.txt

@@ -199,3 +199,4 @@ Krzysztof Bujniewicz, 2015/10/21
 Sukrit Khera, 2015/10/26
 Dave Smith, 2015/10/27
 Dennis Brakhane, 2015/10/30
+Chris Harris, 2015/11/27