public function update($account, $repo, $title, $content, $path = null, $rev = null)
    {
        if (is_null($path)) {
            $path = sprintf('/%s', $title);
        }

        $params = array('data' => $content, 'path' => $path);

        if (!is_null($rev)) {
            $params['rev'] = $rev;
        }

        return $this->requestPut(
            sprintf('repositories/%s/%s/wiki/%s', $account, $repo, $title),
            $params
        );
    }