Consider disabling experimental parts of Draco option by default

[donmccurdy]

I've seen a few bug reports where developers use this tool to Draco-compress their model, and are confused when it doesn't load correctly in KHR_draco_mesh_compression-compliant loaders. Since the extension doesn't allow animation, it might be good to (1) enable only official features on export by default, and (2) clearly mark or disable features that can't be loaded by any official loader.

Thanks!

[donmccurdy]

Wanted to bump this back up, we're still getting reports from our users that their models don't work, and the models seem to come from this tool. The Draco extension does not support morph targets, if you would like an alternative that does I would recommend KhronosGroup/glTF#1830.

[donmccurdy]

/cc @InSimo