Export batch attributes in threejs

Related to #110

src/three/TilesRenderer.js

@@ -478,7 +478,12 @@ export class TilesRenderer extends TilesRendererBase {
 			case 'b3dm':
 				promise = new B3DMLoader( manager )
 					.parse( buffer )
-					.then( res => res.scene );
+					.then( res => {
+
+						res.scene.batchAttributes = res.batchTable.header;
+						return res.scene;
+
+					 } );
 				break;
 
 			case 'pnts':