message: animateNodes callback is now optional
diff: @@ -29,7 +29,7 @@ export function animateNodes(
  graph: Graph,
  targets: PlainObject<PlainObject<number>>,
  opts: Partial<AnimateOptions>,
  - callback: () => void,
  + callback?: () => void,
  ): () => void {
  const options: AnimateOptions = Object.assign({}, ANIMATE_DEFAULTS, opts);
  