currency_rate_update: fix wrong use of timetuple.
- remove error
"TypeError: argument must be 9-item sequence, not datetime.datetime"
currency_rate_update: use date format of openerp.tools.
- DEFAULT_SERVER_DATETIME_FORMAT and DEFAULT_SERVER_DATE_FORMAT
currency_rate_update: fix, forget to add import timedelta
currency_rate_update : mini date fix in currency_rate_update.py
Merge pull request #13 from savoirfairelinux/fix_currency_rate_update-wrong_timedelta

currency_rate_update: fix wrong use of timetuple.