ADC - Soil Evaluation Curve - Coefficent generation undocumented?!

[mrred2k]

As I am testing coatings, and wanted to calibrate the devices based on multiple coatings etc, I couldnt find any documentation on how to produce coeffitions from adc raw soul measurements.
I checked the functions, which are producting the estimated "percentages" but I was not able to change the coeffs in the device tree.

The 3 coefficients are produced somewhere else but I dont know where.

@rbaron Maybe you can help here a little bit. I am more than willing to support you with the docs in some PR.

[rbaron]

@mrred2k indeed the calibration is not very well documented. I tried explaining what I did in #79 (comment) and #79 (comment), but it would be ideal to write a better process for it -- or even better, automate it.