Ability to call methods from Autoload scripts from the AnimationPlayer

[polgar1]

Currently, using the Call method track in the AnimationPlayer, you can only call methods of the nodes that are in the current scene tree. I think it would be useful to be able to call methods from global scripts, to make it easier to use different systems that are autoloaded.

[AThousandShips]

See:

• Add "Autoload" animation tracks to the `AnimationPlayer` #11435