match the convention that foo's uninstall script is uninstall_foo.sql.
Also, stop installing lo_test.sql, which really ought to be made into
a regression test anyway (though it's unclear how to avoid a dependency
on the current OID counter...)

a physically separate type.  Defining 'lo' as a domain over OID works
just fine and is more efficient.  Improve documentation and fix up the
test script.  (Would like to turn test script into a proper regression
test, but right now its output is not constant because of numeric OIDs;
plus it makes Unix-specific assumptions about files it can import.)

only remnant of this failed experiment is that the server will take
SET AUTOCOMMIT TO ON.  Still TODO: provide some client-side autocommit
logic in libpq.

Create objects in public schema.

Make spacing/capitalization consistent.

Remove transaction block use for object creation.

Remove unneeded function GRANTs.

with OPAQUE, as per recent pghackers discussion.  I still want to do some
more work on the 'cstring' pseudo-type, but I'm going to commit the bulk
of the changes now before the tree starts shifting under me ...