public static function view($id)
 {
     self::check_admin_logged_in();
     $user = User::find($id);
     $competitions = array();
     if ($user->type == 'recorder') {
         $competitions = Competition::get_competitions_which_user_has_recording_rights_to($id);
     }
     View::make('user/user.html', array('user' => $user, 'competitions' => $competitions));
 }