Update email-adress in README

Author: Michael Große

README

@@ -13,7 +13,7 @@ Please refer to http://www.dokuwiki.org/plugins for additional info
 on how to install plugins in DokuWiki.
 
 ----
-Copyright (C) Andreas Gohr <gohr@cosmocode.de>
+Copyright (C) Andreas Gohr <dokuwiki@cosmocode.de>
 
 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by