Add `disabled` prop to `List`
Fixes https://github.com/tajo/react-movable/issues/49
This adds a top-level disabled prop to the List component to allow disabling all moves.
I also added isDisabled to the renderItems prop, but it's technically not needed and I'm happy to take it back out if you prefer. I just thought it would be nice to avoid users needing to check both value.disabled and whatever they're using to disable the overall list. I don't feel strongly though.
This is a PR on top of a PR. I recommend merging https://github.com/tajo/react-movable/pull/105 first, otherwise it will get closed along with this PR.
@tajo it looks like Netlify is trying to use a deprecated image, and should be updated.