Fix dumping of DEFERRABLE/INITIALLY DEFERRED:

Fix dumping of DEFERRABLE/INITIALLY DEFERRED:

> The big problem is that while pg_dump's dump_trigger() looks at
> tginitdeferred and dumps accordingly, pg_get_constraintdef doesn't look
> at tginitdeferred, and therefore doesn't record the requirement as part
> of ALTER TABLE ADD CONSTRAINT.

pg_get_constraintdef should probably be looking at condeferrable and
condeferred in the pg_constraint row it's looking at.  Maybe something
like the attached.

(Added, output only non-default values.)

Stephan Szabo