bin/gstlal_bank_splitter: update copyright info

gstlal-inspiral/bin/gstlal_bank_splitter

 #! /usr/bin/env python
 #
 # Copyright (C) 2012 Stephen Privitera
-# Copyright (C) 2011 Chad Hanna
+# Copyright (C) 2011-2014 Chad Hanna
 # Copyright (C) 2010 Melissa Frei
 #
 # This program is free software; you can redistribute it and/or modify it