Lists all DNS records for the given domain
        :param zone: the domain for which records are being retrieved
        :type zone: str
        :return:
        :rtype: generator

def rec_load_all(self, zone):
        """
        Lists all DNS records for the given domain
        :param zone: the domain for which records are being retrieved
        :type zone: str
        :return:
        :rtype: generator
        """
        has_more = True
        current_count = 0
        while has_more:
            records = self._request({
                'a': 'rec_load_all',
                'o': current_count,
                'z': zone
            })
            try:
                has_more = records['response']['recs']['has_more']
                current_count += records['response']['recs']['count']
                for record in records['response']['recs']['objs']:
                    yield record
            except KeyError:
                has_more = False