Support for setting ENVDATA using temperature in C and humidity as percent

[eried]

Simple addition based on https://github.com/sparkfun/SparkFun_CCS811_Arduino_Library/blob/master/src/SparkFunCCS811.cpp

[Joerny]

Unfortunately, this was not compiling on my side. Maybe I had wired settings in the compiler. But changing that to the following code worked for me:

Suggested change

	//Check for invalid temperatures
	temperature = max(-25,min(temperature,50));
	//Check for invalid humidity
	relativeHumidity = max(0,min(relativeHumidity,100));
	//Check for invalid temperatures
	temperature = max(-25.0f,min(temperature,50.0f));
	//Check for invalid humidity
	relativeHumidity = max(0.0f,min(relativeHumidity,100.0f));