Extend onZoom and onPan callbacks for syncing multiple charts

[vbackeberg]

Feature Proposal

I have created a PR that extends the onZoom and onPan callbacks with the amount zoomed/panned.
chartjs/chartjs-plugin-zoom#933

This should help everyone trying to sync zoom and pan accross charts. :)

If you could take a look, I'd much appreciate it.

Possible Implementation

No response

[LeeLenaleee]

Closing as this issue is specific to the zoom plugin and not the Chart.js core