Update all copyright dates.

svn path=/trunk/yasm/; revision=1827
diff --git a/test_hd.c b/test_hd.c
index d917adf..05b53e5 100644
--- a/test_hd.c
+++ b/test_hd.c
@@ -2,7 +2,7 @@
  *
  * Simple hexidecimal dump, two hex digits per line.
  *
- *  Copyright (C) 2004  Peter Johnson
+ *  Copyright (C) 2004-2007  Peter Johnson
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions