Koha::MetadataIterator - iterates over records
This provides a fairly generic iterator that will return records provided by a function.
    use Koha::MetadataIterator;
    my $next_func = sub {
        # something that'll return each record
    };
    my $iterator = Koha::MetadataIterator->new($next_func);
    while ( my $record = $iterator->next() ) {
        # do something with $record
    }
my $it = new($next_func);
Takes a function that will provide the next bit of data.
Provides the next record.