Here is an updated version of this patch which should apply to HEAD,
with updated docs, regression tests, pg_dump and psql \d.
It works well for small numbers of temporary uniqueness violations,
and at least as well (in fact about twice as fast) as deferred FK
checks for large numbers of deferred checks.
I propose trying to improve performance and scalability for large
numbers of deferred checks in a separate patch.
- Dean
