Update copyright line to 2015
diff --git a/include/polarssl/base64.h b/include/polarssl/base64.h
index 0c24446..db95cb1 100644
--- a/include/polarssl/base64.h
+++ b/include/polarssl/base64.h
@@ -3,7 +3,7 @@
  *
  * \brief RFC 1521 base64 encoding/decoding
  *
- *  Copyright (C) 2006-2010, ARM Limited, All Rights Reserved
+ *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
  *
  *  This file is part of mbed TLS (https://polarssl.org)
  *