misinformation in docs about modules

[munrocket]

No description provided.

Changed my mind...

[Mugen87]

I think it's better to only advocate the ES6 approach and remove the others. Besides, the following line needs a change otherwise user will get a runtime error when copy/paste the code.

https://github.com/mrdoob/three.js/pull/17076/files#diff-b272ae25a77c61d4e305bea9106871afR107

var loader = new THREE.GLTFLoader(); has to be var loader = new GLTFLoader();

[munrocket]

and remove the others

After that we will need to change all documentation. I will add two additional words before example of code to be fully correct.

[munrocket]

If you want that we can edit all examples in documentation one by one and add LoadingManager to them also.

[Mugen87]

Okay, it's fine like that.

[mrdoob]

Thanks!