$error = FS::cust_pkg::order( $custnum, \@pkgparts );
$error = FS::cust_pkg::order( $custnum, \@pkgparts, \@remove_pkgnums ] );
$error = FS::cust_pkg::order( $custnum, \@pkgparts );
$error = FS::cust_pkg::order( $custnum, \@pkgparts, \@remove_pkgnums ] );