Prepare release 4.0.0

CHANGELOG

@@ -1,3 +1,5 @@
+Version 4.0.0 - 2016-05-02
+* Bug fixes (see mercurial logs for details)
 * Move purchase request to purchase_request module
 * Add Python3 support
 * Add searcher on purchase

COPYRIGHT

@@ -1,7 +1,7 @@
 Copyright (C) 2013-2015 NaN-tic.
-Copyright (C) 2008-2015 Cédric Krier.
+Copyright (C) 2008-2016 Cédric Krier.
 Copyright (C) 2008-2013 Bertrand Chenal.
-Copyright (C) 2008-2015 B2CK SPRL.
+Copyright (C) 2008-2016 B2CK SPRL.
 
 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

tryton.cfg

@@ -1,5 +1,5 @@
 [tryton]
-version=3.9.0
+version=4.0.0
 depends:
     account
     ir