Sort by depositing user doesn't sort alphabetically - because it is sorting by userid

[tmb]

Feedback from NORA training course 01/05/07

[tdb01r]

Resolved by r5795.

{
name => "userid",
type => "itemref",
datasetid => "user",
required => 0,
replace_core => 1,
make_value_orderkey => sub {
    my( $field, $value, $repo, $langid, $dataset ) = @_;

    my $user = $field->get_item( $field->repository, $value );
    return "" if !defined $user;

    return $user->dataset->field( "name" )->ordervalue(
        $user->value( "name" ),
        $repo,
        $langid,
        $dataset
    );
},
},