Add element parameter to onStart and onDone callbacks

[jgmcelwain]

I ran into a situation where I wanted to add a class to an element after it had been scrolled to. Adding the element as a param of the onStart and onDone callback feels like a good way to make this possible.

[rigor789]

Sure why not, but i would add it to the onCancel callback as a second parameter as well, can you add it or do you want me to do it after I merge this?

[rigor789]

Perfect! Thanks 👍