Conflicting option checking in pg_restore

Checking for conflicting options in pg_restore was mostly done in main() with
one check deferred until RestoreArchive().  Reading the git history makes it
seem like it simply happened, without the disjoint checking being intentional.
Am I reading it right that we can consolidate all the option checking to
main()?  The attached patch does that, and also rewords the error message to
make it similar to the other option checks.

cheers ./daniel