It turns out we already have the support since it uses the same axis as
the "wheel", used by other devices (for instance the Airbrush pen of
Wacom has a wheel reporting on this same axis).
We can't do any fancy support for this right now, but at least we can
clarify a bit the dynamics naming so that people understands it can be
used for both wheel and rotation input.
Fix the various "Wheel" dynamics strings into "Wheel/Rotation".