JSON output:
[{"allday":"true","url":"\/rfc_show\/10000","title":"Morkelgrenen lyser gult","id":"10000","end":"2015-10-09 22:45:00","start":"2015-10-09 08:00:00"}]

sub rfc_kal_events {
    my $self = shift;

    my $kal_start = $self->param('start');
    my $kal_end = $self->param('end');

    my $rfc_kal_events = db_rfc_kal_events($kal_start, $kal_end);

    $self->render(json => $rfc_kal_events);
}