SimHub XY properties plot

[blekenbleu]

This SimHub plugin was motivated by JSONio SimHub plugin
configured to support a ShakeIt Bass Shaker profile for tire slip/grip.
It helps evaluate whether two properties are correlated, e.g.:

... and for this case of grip vs slip suggests that slip > 10 (arbitrary units) is excessive.

As release notes indicate, the plugin requires an entry in Simhub\NCalcScripts\ :

[ExportEvent]
name='CarChange'
trigger=changed(200, [DataCorePlugin.GameData.CarId])

.. and a corresponding event trigger mapping:

Sliders above the plot constrain a sample sequence to contain
at least one X value less than the left slider
and at least one X value greater than the right slider.
The Refresh button does not appear until those requirements are met.