development: use new keyframe support of vizzu + add slider

[simzer]

Vizzu now supports multiple animations in a single animation call:

chart.animate(
 [
  {
    target: { data, chart, style },
    options: animOptions
  },
  ...
],
animopts)

Note: this feature is not released yet, but available from commit vizzuhq/vizzu-lib@3b73f2f
Available online here: https://vizzu-lib-main-sha.storage.googleapis.com/lib-3b73f2f/vizzu.js

The benefit of using this to pass slide phases together in one animate() call is that vizzu will consider this as a single animation.
This way adding a slider which can seek through all the phases becomes more simple.

[simzer]

Also, with this change: vizzuhq/vizzu-lib@03653ad, the whole animation (containing start, end, intermediate charts + anim options) can be stored and restored. Using this feature could simplify the current code.
Vizzu version hosted here: https://vizzu-lib-main-sha.storage.googleapis.com/lib-03653ad/vizzu.js
Example code repeating the previous animation:

chart.animate(...).then(chart => chart.animate(chart.animation.store()))

[dyuri]

@simzer I've removed the sub-slide concept and switched to keyframes - see my PR. Looks fine here.
I'd add the slider in a second step, but if this part works then it should be quite straightforward.

[simzer]

The animation control interface is changed. The animate method returns a promise, which still resolves when the animation is finished, but it does not incorporate the control methods. Instead, it contains another promise called 'activated', which resolves to the controller object when the animation starts.
See https://lib.vizzuhq.com/0.7/tutorial/animation_control_keyframes/

So doing something at the beginning of the animation looks like this:

chart.animate({...}).activated.then(control => ...);

For example storing the whole animation (start and end chart and the animation options between them:

var animation;
chart.animate({...}).activated.then(control => {
    animation = control.store();
});

Then resetting to a previously stored animation:

chart.animate(animation)

See: https://lib.vizzuhq.com/0.7/tutorial/shorthands_store/

[simzer]

sorry, wrong issue, comment removed.

[simzer]

After discussion with @dyuri:
Fix needed in vizzu lib, to allow reverse playing of stored animation. see vizzuhq/vizzu-lib#166

[simzer]

vizzuhq/vizzu-lib#166 fixed

Animation can be played in reverse using these options:

chart.animate(anim, { position: 1, direction: 'reverse' });

Working example: https://jsfiddle.net/simzer/tfmjsunr/19/
pre-release url: https://vizzu-lib-main-sha.storage.googleapis.com/lib-66a2735/vizzu.js