Re: superuser() shortcuts

Thanks!  Please add it to the next commitfest.

I don't think has_rolinherit or has_rolcatupdate really need to move and
it seems unlikely that they'd be needed from elsewhere..  Is there a
reason you think they'd need to be exposed?  I've not looked at the
patch at all though, perhaps that makes it clear.

> * has_createrole_privilege
> * has_bypassrls_privilege
These are already in the right place, right?

> * has_inherit_privilege
> * has_catupdate_privilege

These probably don't need to move as they're only used in the .c files
that they're defined in (unless there's a reason that needs to change).

> * has_???_privilege

Right, other things might be 'has_backup_privilege', for things like
pg_start/stop_backup and friends.