Animatable Nodes

Created by: vicdoval

Right now when the frame changes a global update is performed which is bad idea because many parts of the node tree may not change during the animation. I propose to add a is_animatable property to the nodes that can be affected by a scene change, (Objects in, F-Curve, Objects Id selector...) so when the frame change is done the system calls process_from_animatable in stead of a global process. This property could be exposed in the N-Panel properties (enabled by default) so the user can disable it in the desired node to make the animation faster