Fix period selection around midnight to follow timezone

--HG-- branch : 16.0

models/account_move.py

@@ -42,7 +42,7 @@ class AccountMove(models.Model):
 
     def fill_period(self):
         """Find an open period around move date, set it onto that move."""
-        today = fields.Date.today()
+        today = fields.Date.context_today(self)
 
         for accdoc in self:
             acc_date = accdoc.date or today