Include data format in register address

[kriskeillor]

The I2C register map does not define the data format, and the listed examples use different ways of calculating them.

E.g., the example by Daniel Tamm and Jasper Wallace simply prints the raw registers as Temp (C or F?), Moisture (Relative Humidity?), and Light (Lux?). Meanwhile, the example from krikk (second code block following above anchor link) treats light and moisture as raw values, while temp is divided by ten.

All in all, the data format and unit of the sensor readings needs to be provided in the I2C register map (or somewhere else).