proposal, better fk joint rotation

[slikdigit]

interesting- I don't remember A:M working in this way, but its been a while since I've used it. I do remember some nice features (Aditional constraints, constraint offsets, offset mode and of course, the abilitiy to have Editing data and interpolation data distinct- Its nice to have quaternion interpolated bones that you can edit as euler angles, for instance- for that matter, handy having a choice in what type of interpolation to use (quat is not always the best)