owncloud / updater

		// has to be installed

		$file = $locator->getPathToConfigFile();

		if (!file_exists($file) || !is_file($file)){

			throw new \RuntimeException('ownCloud in ' . dirname(dirname($file)) . ' is not installed.');

		}

		// version.php should exist

		$file = $locator->getPathToVersionFile();

		// version.php should exist

		$file = $locator->getPathToVersionFile();

		if (!file_exists($file) || !is_file($file)){

			throw new \RuntimeException('ownCloud is not found in ' . dirname($file));

		}

		// datadir should exist

		$dataDir = $locator->getDataDir();