[FIX] event: located dates in events name

The user timezone wasn't respected in the events name.

e.g. for a user with timezone UTC+1,
for an event
from 12/01/2015 00:00:00
to   12/02/2015 00:00:00
The dates in the event name were set to
(2015-11-30 - 2015-12-01)
while it must be
(2015-12-01 - 2015-12-02)

opw-657962

addons/event/event.py

@@ -201,7 +201,9 @@ class event_event(models.Model):
     def name_get(self):
         result = []
         for event in self:
-            dates = [dt.split(' ')[0] for dt in [event.date_begin, event.date_end] if dt]
+            date_begin = fields.Datetime.from_string(event.date_begin)
+            date_end = fields.Datetime.from_string(event.date_end)
+            dates = [fields.Date.to_string(fields.Datetime.context_timestamp(event, dt)) for dt in [date_begin, date_end] if dt]
             dates = sorted(set(dates))
             result.append((event.id, '%s (%s)' % (event.name, ' - '.join(dates))))
         return result