public function load($collection = null)
    {

        $items = array();

        $list = DB::table($this->table);

        if ($collection !== null) {
            $list = $list->where('key', 'LIKE', $collection . '%');
        }

        $list = $list->pluck('value', 'key');


        // convert dotted list back to multidimensional array
        foreach ($list as $key => $value) {
            $value = json_decode($value);
            array_set($items, $key, $value);
        }

        return $items;
    }