public function createService( ServiceLocatorInterface $serviceLocator )
    {
        // Configure the definitions
        $config     = $serviceLocator->get( 'Configuration' );
        $coreConfig = isset( $config['modules']['Grid\Core'] )
                    ? (array) $config['modules']['Grid\Core']
                    : array();

        return new EnabledList(
            isset( $coreConfig['enabledPackages'] )
                ? (array) $coreConfig['enabledPackages']
                : array(),
            isset( $coreConfig['modifyPackages'] )
                ? (bool) $coreConfig['modifyPackages']
                : true
        );
    }