model getter and setter functionality
in model
    public function getAuthorId($value)
    {
        return $author_id."dfdsf";
    }

    public function setAuthorId($value)
    {
        return ++$author_id."dfdsf";
    }

requesting values
    foreach(Model_News::find_all() as $m) {
      var_dump($m->author_id);
      $m->author_id = 545;
      var_dump($m->author_id);
    }

Signed-off-by: pussbb <pussbb@gmail.com>