Update copyright dates (20XY-2012 ==> 20XY-2013)


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13658 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/helgrind/libhb_core.c b/helgrind/libhb_core.c
index 8f30fe5..d2047c6 100644
--- a/helgrind/libhb_core.c
+++ b/helgrind/libhb_core.c
@@ -9,7 +9,7 @@
    This file is part of LibHB, a library for implementing and checking
    the happens-before relationship in concurrent programs.
 
-   Copyright (C) 2008-2012 OpenWorks Ltd
+   Copyright (C) 2008-2013 OpenWorks Ltd
       info@open-works.co.uk
 
    This program is free software; you can redistribute it and/or