Support for official Openness

As of Varjo Base & Native SDK 3.7, Varjo offers an official Openness Value for the eye tracking. This build/release includes support for that.
The Value is parsed into the 3 SRanipal Parameters concerning the eye lids (Eye Openness, Eye Squeeze, Eye Widen).
Thresholds for this parsing is for the time being is hardcoded to values that seemed alright during my testing (for custom values, you'll need a custom build for the time being)