I think it's more natural if animation do not perform so often. Once per second looks better imho and it's a better example of this library usage.
Also, removed animations if "fetch" is finished
## Motivation
I attach example illustrating this issue. The problem appears when we use `evaluateOnce` method (e.g. via `setValue`) for updating node which could be detached in the same time.
## Changes
I observe I haven't deeply understood flow of reanimataed while writing this logic. Actually always node representing evaluation should not have children which has be informed about changes (it's pointless). In fact, always node has to be a child of these nodes, because we want to have these nodes attached (make them not sensitive for other detachments), because they states input for given node.
