glTF asset import enhancements

[slimbuck]

This issue lists high-level work items still remaining to fully support editor glTF import in roughly priority order:

Support loading:

• node hierarchy
• mesh/primitive data
• standard material
• ratified material extensions
• animated skeletons and skinning data
• morph targets
• cameras
• draco compressed models
• light support KHR_lights_punctual

[yaustar]

Material, model and animation support in Release 1.24.0
https://blog.playcanvas.com/gltf-import-arrives-in-the-playcanvas-editor/

GLB.Asset.Import.Loop.v2.mp4

GLB.Import.Fox.Animation.mp4

[slimbuck]

This work is now done. A follow up ticket will list additional future work.

[NworbLegin]

There is a bug in the KHR_lights_punctual import from glTF/glb where a point light is imported with an incorrect rotation setting and the inner and outer radius values have not been converted from radians to degrees.

Rotation: It looks like a point light is imported with an additional rotation of -90 degrees on the x axis
Inner/Outer Radius: These values have not been converted from radians in the glTF to the degree values required for the Editor light value.