Improve animation of the 'publish' button

The Publish button in the Visual Editor has a small 'bump' effect when it's rendered, to grab the users attention. Initial feedback made clear that this animation is not prominent enough to grab the users attention: the publication state icon in the top right corner also changes, in an animated way, which is much more noticeable than the animation of the Publish button. As a result, users miss the new Publish button completely.

We should change the animation to something more noticeable.