[Fearture Request] Blending support improvement

Much of this may already be covered here:

I just want to add my own spin.

  • I would like to be able to set default Blend Settings directly on the State Machine node in the AnimGraph, as a fallback for all Transitions.
  • Blend Settings on the State Machine node might be nice to have optionally as Pins.
  • In the Anim Graph, we can currently set Blend Settings on each Transition, but if those values could be set within the rule, directly on the Result node, those values could also be set as Pins.
  • The spring blend should support a stiffness / dampening parameter.

I would like to see the options for new blends on other nodes as well, but the above opens up a lot of semi-procedural options for quickly prototyping.