Prepare release 6.4.0 [skip ci]

CHANGELOG

@@ -1,3 +1,5 @@
+Version 6.4.0 - 2022-05-02
+* Bug fixes (see mercurial logs for details)
 * Add support for Python 3.10
 * Remove support for Python 3.6
 

COPYRIGHT

@@ -1,5 +1,5 @@
-Copyright (C) 2018-2021 B2CK
-Copyright (C) 2019-2021 Cédric Krier
+Copyright (C) 2018-2022 B2CK
+Copyright (C) 2019-2022 Cédric Krier
 Copyright (C) 2018-2019 Nicolas Êvrard
 
 This program is free software: you can redistribute it and/or modify

tryton.cfg

@@ -1,5 +1,5 @@
 [tryton]
-version=6.3.0
+version=6.4.0
 depends:
     ir
 xml: