Update copyright PSF to 2001-2017 (#3421)

Signed-off-by: Christian Heimes <christian@python.org>
diff --git a/README.rst b/README.rst
index 4829271..b7e9eff 100644
--- a/README.rst
+++ b/README.rst
@@ -233,7 +233,8 @@
 ---------------------------------
 
 Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011,
-2012, 2013, 2014, 2015, 2016 Python Software Foundation.  All rights reserved.
+2012, 2013, 2014, 2015, 2016, 2017 Python Software Foundation.  All rights
+reserved.
 
 Copyright (c) 2000 BeOpen.com.  All rights reserved.