Make histogram interactive in DomainSlider

[loichuder]

That could have been as simple as adding this line.

But due to airbnb/visx#1174, the point positions when dragging are wrongly computed as the domain slider root div is translated via transform. The purpose of the transform was to center the tooltip with respect to the slider.

Therefore, I reimplemented the centering by adding a flex container around the slider container and the tooltip to center them. This allows to remove transform from the histogram hierarchy of parents to work around airbnb/visx#1174.

[loichuder]

There appears to be a little mismatch between the two implementations:

[axelboc]

The div inside which the tooltip used to be has margin-right: -0.375rem;. So moving it out of this element shifts the tooltip to the left by this amount, which means that it is now more centered than it was before 💯 😄

[loichuder]

/approve