X axis should be on 0 as datum

**Is your feature request related to a problem? Please describe.**
I would like to make zero the point of reference for any axes if there are positive and negative values.

see https://elastic.github.io/elastic-charts/?path=/story/bar-chart--scale-to-extent

**Describe the solution you'd like**
The x and or y-axis lines should be on zero as datum.

**Kibana Cross Issues**
Add any [Kibana](https://github.com/elastic/kibana) related issues/feature requests here.

**Checklist**

- [ ] this request is checked against already exist requests
- [ ] every related Kibana issue is listed under `Kibana Cross Issues` list
- [ ] `kibana cross issue` tag is associated to the issue if any kibana cross issue is present

No file, test, or entry point is named. Start by reproducing the linked scale-to-extent bar-chart example and inspect how axes are positioned for mixed positive and negative values; done means the relevant x and/or y axis line uses zero as its datum.

Written by the indexing model from the issue text.