Extending grant insert on tables to sequences

Hi,

The idea of this patch is to avoid the need to make explicit grants on
sequences owned by tables.

This patch make:
- GRANT INSERT ON TABLE  extend to GRANT USAGE ON SEQUENCE    (currval, nextval)
- GRANT UPDATE ON TABLE extend to GRANT UPDATE ON SEQUENCE (nextval, setval)
- GRANT SELECT ON TABLE extend to GRANT SELECT ON SEQUENCE  (currval)

comments?

--
regards,
Jaime Casanova
Soporte y capacitación de PostgreSQL
Guayaquil - Ecuador
Cel. (593) 087171157