Add copyright info for files by Simon Josefsson.

etc/images/gnus/README

 COPYRIGHT AND LICENSE INFORMATION FOR IMAGE FILES
 
+Files: important.xpm, unimportant.xpm
+Author: Simon Josefsson <simon@josefsson.org>
+Copyright (C) 2001 Free Software Foundation, Inc.
+License: GNU General Public License version 2 or later (see COPYING)
+
 Files: catchup.pbm catchup.xpm cu-exit.pbm cu-exit.xpm
   describe-group.pbm describe-group.xpm exit-gnus.pbm exit-gnus.xpm
   exit-summ.pbm exit-summ.xpm followup.pbm followup.xpm fuwo.pbm
-  fuwo.xpm get-news.pbm get-news.xpm mail-reply.pbm mail-reply.xpm
-  next-ur.pbm next-ur.xpm post.pbm post.xpm prev-ur.pbm prev-ur.xpm
-  preview.xbm preview.xpm receipt.xpm reply-wo.pbm reply-wo.xpm
-  reply.pbm reply.xpm save-aif.pbm save-aif.xpm save-art.pbm
-  save-art.xpm subscribe.pbm subscribe.xpm unsubscribe.pbm
-  unsubscribe.xpm uu-decode.pbm uu-decode.xpm uu-post.pbm uu-post.xpm
+  fuwo.xpm get-news.pbm get-news.xpm gnntg.pbm gnntg.xpm
+  mail-reply.pbm mail-reply.xpm next-ur.pbm next-ur.xpm post.pbm
+  post.xpm prev-ur.pbm prev-ur.xpm preview.xbm preview.xpm receipt.xpm
+  reply-wo.pbm reply-wo.xpm reply.pbm reply.xpm save-aif.pbm
+  save-aif.xpm save-art.pbm save-art.xpm subscribe.pbm subscribe.xpm
+  unsubscribe.pbm unsubscribe.xpm uu-decode.pbm uu-decode.xpm
+  uu-post.pbm uu-post.xpm
 Author: Luis Fernandes <elf@ee.ryerson.ca>
 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
   Free Software Foundation, Inc.