Add bone scaling functions

[DryxioGTA]

Adds functions to scale ped bones:

• setElementBoneScale(ped, bone, scaleX, scaleY, scaleZ)
• getElementBoneScale(ped, bone)
• resetElementBoneScale(ped, bone)
• resetAllElementBoneScales(ped)

Related : #3123

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Thank you!

[Fernando-A-Rocha]

Awesome feature!

To avoid having an additional function for resetting all bones of a ped, I think resetElementBoneScale could be adapted to do that if no 2nd bone argument is passed.