public function createManifest(Package $package)
    {
        $manifestData = array();
        foreach (Package::$packageFiles as $rawFile) {
            $filePath = sprintf('%s/%s', $package->getPackageDir(), $rawFile);
            $manifestData[$rawFile] = sha1(file_get_contents($filePath));
        }

        $manifestJsonPath = sprintf('%s/manifest.json', $package->getPackageDir());
        $manifestJson = json_encode((object) $manifestData);

        file_put_contents($manifestJsonPath, $manifestJson);

        return $manifestJsonPath;
    }