public function getConfigTreeBuilder()
    {
        $treeBuilder = new TreeBuilder();
        $rootNode = $treeBuilder->root('victoire_seo');

        $rootNode
            ->addDefaultsIfNotSet()
            ->children()
                ->arrayNode('analytics')
                    ->useAttributeAsKey(true)
                    ->prototype('array')
                    ->children()
                        ->booleanNode('enabled')->defaultValue('false')->end()
                        ->scalarNode('key')->defaultNull()->end()
                    ->end()
                ->end()
                ->end()
            ->end();

        return $treeBuilder;
    }