Coat and Fuzz parameter order inconsistent between specification and reference implementation

[JGamache-autodesk]

Clearly a very minor detail, but the reference implementation has Fuzz before Coat while the specification has Coat before Fuzz in the parameter reference.

[JGamache-autodesk]

The Emission and Thin Film sections are also swapped between spec and reference implementation.

[portsmouth]

I think coat before fuzz makes more sense for OpenPBR, since we generally order the parameters from the base upwards.

Having emission before thin-film (and thin-film after fuzz) doesn't seem particularly logical though. Arguably the emission should be just before the coat (since the coat tints the emission):

We put emission below the coating so that emitted light will be tinted due to the absorption in the coat and fuzz layers.

And the thin-film should be just before the emission, since it lies above the base, but does not tint the emission.