blendshape restriction

[Benjythebee]

Add the ability to bring in Blendshape restrictions on a trait basis:

adds restrictedBlendshapes in traitRestrictions; for example:

  "traitRestrictions":{
    "jackets":{
      "restrictedTraits":["mask"],
      "restrictedTypes":[]
    },
    "mask":{
      "restrictedTraits":[],
      "restrictedTypes":[],
      "restrictedBlendshapes":["body"]
    }
  },

What does it do?

If I have:

    "A":{
      "restrictedBlendshapes":["B"]
    }

Then loading A will disable the blendshapes of B.