secure http -> https redirect in master config (EE)

https redirect

    /**
     * Force HTTPS on prod & staging. This functionality was previously in the .htaccess'es but we moved
     * it here to ease multiple environment development.
     */
    if(FORCE_HTTPS && (!isset($_SERVER['HTTPS']) || $_SERVER['HTTPS'] == "")){
        $redirect_url = filter_var("https://".$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI'], FILTER_VALIDATE_URL);
        if($redirect_url) {
            header("HTTP/1.1 301 Moved Permanently"); 
            header("Location: $redirect_url");
            die();
        } else {
            die('Please use HTTPS equivalent of this URL.');
        }
    }