pgsql: Always pass catalog id to the options validator function

Log Message:
-----------
Always pass catalog id to the options validator function specified in
CREATE FOREIGN DATA WRAPPER. Arguably it wasn't a bug because the
documentation said that it's passed the catalog ID or zero, but surely
we should provide it when it's known. And there isn't currently any
scenario where it's not known, and I can't imagine having one in the
future either, so better remove the "or zero" escape hatch and always
pass a valid catalog ID. Backpatch to 8.4.

Martin Pihlak

Modified Files:
--------------
pgsql/doc/src/sgml/ref:
create_foreign_data_wrapper.sgml (r1.5 -> r1.6)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_foreign_data_wrapper.sgml?r1=1.5&r2=1.6)
pgsql/src/backend/commands:
foreigncmds.c (r1.8 -> r1.9)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/foreigncmds.c?r1=1.8&r2=1.9)
pgsql/src/backend/foreign:
foreign.c (r1.5 -> r1.6)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/foreign/foreign.c?r1=1.5&r2=1.6)
pgsql/src/test/regress/expected:
foreign_data.out (r1.11 -> r1.12)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/foreign_data.out?r1=1.11&r2=1.12)