Change copyright messages to include 2013.
diff --git a/Makefile b/Makefile
index 5cbc94b..c9cdb90 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-# dnsmasq is Copyright (c) 2000-2012 Simon Kelley
+# dnsmasq is Copyright (c) 2000-2013 Simon Kelley
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by