Prepare release 5.6.0 [skip ci]

CHANGELOG

@@ -1,3 +1,5 @@
+Version 5.6.0 - 2020-05-04
+* Bug fixes (see mercurial logs for details)
 * Add cron job to supply stock
 
 Version 5.4.0 - 2019-11-04

COPYRIGHT

@@ -1,7 +1,7 @@
 Copyright (C) 2013-2019 NaN-tic.
-Copyright (C) 2008-2019 Cédric Krier.
+Copyright (C) 2008-2020 Cédric Krier.
 Copyright (C) 2008-2013 Bertrand Chenal.
-Copyright (C) 2008-2019 B2CK SPRL.
+Copyright (C) 2008-2020 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=5.5.0
+version=5.6.0
 depends:
     account
     ir