[charts] Support "off the charts" chart values

[TheOneTheOnlyJJ]

Summary

A new way of presenting extreme data should be supported, allowing chart data to be rendered "outside" the chart.
To make this possible, specialized graphical elements must be added, like the dotted line and its interruption below.

Examples

Imagine, for example, how small the visible line variance from the chart above would become if the peak value were represented in a standard fashion.

Motivation

When such extreme data has to be displayed, simply scaling the chart to fit it linearly will cause the non-extreme data to become inaccessible to the viewer.

Search keywords: off the charts chart values customization new feature

[JCQuintas]

This seems quite complex to do in our current library.

An alternative is to provide the entire data to the graph and have zoom filtering enabled, as well as a custom component to allow the user to pick only slices of the data

[michelengelen]

@JCQuintas should we still explore this?

[JCQuintas]

I would be interested in seeing what @alexfauquette has to say, but I suppose this is a very niche use-case.

[alexfauquette]

For me the best we could do is the following. Allowing to specify some gaps in the a x/y axes.

[TheOneTheOnlyJJ]

This is satisfactory, especially if #15477 will allow marking such extreme values to highlight them. This issue may even make more sense bundled with #15477.