remove_right can now take None as index to remove all rules.

        Remove a right rule from the provided account.

        :param login: the login of the account

        :param index: the index of the rule to delete

        :param index: the index of the rule to delete or None for all rules

        '''

        conf = self._get_conf(login)

        rights = conf['rights']

        if index is None:

            conf['rights'] = []

        else:

            try:

            rights.pop(index)

                conf['rights'].pop(index)

            except IndexError:

            raise CCConf.OutOfRangeIndexError('Bad rule index %s' % repr(index))

                raise CCConf.OutOfRangeIndexError('Bad rule index '

                                                  '%s' % repr(index))

        self._set_conf(login, conf)

    def list_accounts(self):