public function sendHeaders($cookies_also = true, $override = false)
    {
        if (headers_sent() && !$override) {
            return $this;
        }

        // Send our HTTP status line
        header($this->httpStatusLine());

        // Iterate through our Headers data collection and send each header
        foreach ($this->headers as $key => $value) {
            header($key .': '. $value, false);
        }

        if ($cookies_also) {
            $this->sendCookies($override);
        }

        return $this;
    }