Expose effective tooltip position as a class on the tooltip component

[alirezamirian]

Please describe the feature you would like to request.

Expose effective tooltip position as a class on the tooltip component

What is the use-case or motivation for this proposal?

This enables appearance customizations like adding triangles to all tooltips with a simple css, based on position classes.

Is there anything else we should know?

It's important to consider effective position, which is not necessarily equal to one which is passed as input.