get_user inconsistence

[helpse]

At this file:
https://github.com/open-classifieds/common/blob/master/classes/auth/oc.php

 /**
 * Gets the currently logged in user from the session (with auto_login check).
 * Returns FALSE if no user is currently logged in.
 *
 * @return  mixed
 */
public function get_user($default = NULL)
{
    $user = parent::get_user($default);

    if ( ! $user)
    {
        // check for "remembered" login
        $user = $this->auto_login();
    }

    return $user;
}

parent::get_user() is returning NULL by default and auto_login() is returning FALSE.
We should use public function get_user($default = FALSE) to get a consitency.

[neo22s]

I agree! this also meas a bit of refactor for each time we do ``if (Auth::instance()->get_user()`