Add copyright and fix description for some sources

src/ejabberd_cluster.erl

@@ -1,10 +1,24 @@
 %%%-------------------------------------------------------------------
 %%% @author Evgeny Khramtsov <ekhramtsov@process-one.net>
-%%% @copyright (C) 2017, Evgeny Khramtsov
-%%% @doc
-%%%
-%%% @end
 %%% Created :  5 Jul 2017 by Evgeny Khramtsov <ekhramtsov@process-one.net>
+%%%
+%%%
+%%% ejabberd, Copyright (C) 2002-2017   ProcessOne
+%%%
+%%% 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 the Free Software Foundation; either version 2 of the
+%%% License, or (at your option) any later version.
+%%%
+%%% This program is distributed in the hope that it will be useful,
+%%% but WITHOUT ANY WARRANTY; without even the implied warranty of
+%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+%%% General Public License for more details.
+%%%
+%%% You should have received a copy of the GNU General Public License along
+%%% with this program; if not, write to the Free Software Foundation, Inc.,
+%%% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+%%%
 %%%-------------------------------------------------------------------
 -module(ejabberd_cluster).
 -behaviour(ejabberd_config).

src/ejabberd_cluster_mnesia.erl

@@ -1,7 +1,7 @@
 %%%----------------------------------------------------------------------
-%%% File    : ejabberd_cluster.erl
+%%% File    : ejabberd_cluster_mnesia.erl
 %%% Author  : Christophe Romain <christophe.romain@process-one.net>
-%%% Purpose : Ejabberd clustering management
+%%% Purpose : Ejabberd clustering management via Mnesia
 %%% Created : 7 Oct 2015 by Christophe Romain <christophe.romain@process-one.net>
 %%%
 %%%