Blender Exporter: Added link to help people that still need it.

Author: mrdoob

utils/exporters/blender/README.md

@@ -1,3 +1,5 @@
 # Three.js Blender Export
 
-> **NOTICE:** The Blender exporter for the Three.js JSON format has been removed, to focus on better support for other workflows. For recommended alternatives, see [Loading 3D Models](https://threejs.org/docs/#manual/introduction/Loading-3D-models). The Three.js Object/Scene JSON format is still fully supported for use with [Object3D.toJSON](https://threejs.org/docs/#api/core/Object3D.toJSON), the [Editor](https://threejs.org/editor/), [THREE.ObjectLoader](https://threejs.org/docs/#api/loaders/ObjectLoader) and [converters](https://github.com/mrdoob/three.js/tree/dev/utils/converters).
+> **NOTICE:** The Blender exporter for the Three.js JSON format has been removed, to focus on better support for the glTF workflow. For recommended alternatives, see [Loading 3D Models](https://threejs.org/docs/#manual/introduction/Loading-3D-models). The Three.js Object/Scene JSON format is still fully supported for use with [Object3D.toJSON](https://threejs.org/docs/#api/core/Object3D.toJSON), the [Editor](https://threejs.org/editor/), [THREE.ObjectLoader](https://threejs.org/docs/#api/loaders/ObjectLoader) and [converters](https://github.com/mrdoob/three.js/tree/dev/utils/converters).
+>
+> If you really need the Blender Exporter you can [go back in time to r92](https://github.com/mrdoob/three.js/tree/r92).