Update documentation to describe what method params do

[TytaniumDev]

I've noticed that a lot of the methods in the generated Dart API docs for Flare-Flutter don't have descriptions about what the parameters actually do. Example: https://pub.dev/documentation/flare_dart/latest/animation_actor_animation/ActorAnimation/apply.html

I had to find the actual documentation for apply in a medium post: https://medium.com/2dimensions/building-a-responsive-house-with-flare-flutter-31af823ba805

The description in the Medium post is excellent, it would be great to put those descriptions directly in the dart docs!

I've noticed this in other places in the docs as well, it'd be good to do an audit?

[jkurtw]

/cc @luigi-rosso

[luigi-rosso]

We're working on this!

[she-who-codes]

We recently published our Runtime Manual here. We are continuing to build on it, but it's consolidated a lot of the information we had spread about in our tutorials.

[luigi-rosso]

Let's keep this issue open to specifically track the Dart API documentation in Flare-Flutter! We still have a long way to go there.