update copyright notice

Author: Will Estes

COPYING

@@ -2,7 +2,7 @@ Flex carries the copyright used for BSD software, slightly modified
 because it originated at the Lawrence Berkeley (not Livermore!) Laboratory,
 which operates under a contract with the Department of Energy:
 
-Copyright (c) 2001 by W. L. Estes <[email protected]>
+Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007 The Flex Project.
 
 Copyright (c) 1990, 1997 The Regents of the University of California.
 All rights reserved.