private static function buildCoreFiles($bundleDir, $applicationName, Filesystem $filesystem)
    {
        $filesystem->setParameters(array(
            'namespace' => $applicationName . '\\Bundle\\CoreBundle',
            'applicationName' => $applicationName,
            'rename' => array(
                'Bundle.php.twig' => $applicationName . 'CoreBundle.php',
                'Extension.php.twig' => $applicationName . 'CoreExtension.php',
                'app.yml.twig' => strtolower($applicationName) . '.yml',
            )
        ));

        $filesystem->mirror(__DIR__.'/../Resources/skeleton/avoo-core-bundle', $bundleDir, null, array('override' => true));
    }