feat(modal): Prevent wheel event on modal backdrop

In my opinion, it should not be possible to scroll on the page when modal is displayed. Mostly user does not want to do that. If you disagree, let's make it configurable. But there should be a way to disable it.

I did not write unit tests, since I'm not sure it's worth it (simulating wheel event and checking it was prevented), but I'll be happy to add them.