fix the copyright string years

Makefile.dist

@@ -5,7 +5,7 @@
 #                            | (__| |_| |  _ <| |___ 
 #                             \___|\___/|_| \_\_____|
 #
-# Copyright (C) 2002, Daniel Stenberg, <daniel@haxx.se>, et al.
+# Copyright (C) 1998 - 2004, Daniel Stenberg, <daniel@haxx.se>, et al.
 #
 # In order to be useful for every potential user, curl and libcurl are
 # dual-licensed under the MPL and the MIT/X-derivate licenses.