edycommits/kotlinapi

#Thermostat

Thermostat starts at 20 degrees

You can increase the temperature with an up function

You can decrease the temperature with a down function

The minimum temperature is 10 degrees

If power saving mode is on, 
the maximum temperature is 25 degrees

If power saving mode is off,
 the maximum temperature is 32 degrees

Power saving mode is on by default

You can reset the temperature to 20 with a reset function

You can ask about the thermostat's current energy usage:
< 18 is low-usage,  
< 25 is medium-usage, anything else is high-usage.

Display temperatutre on the screen.

(In the challenges where we add an interface, low-usage will be indicated  
with green, medium-usage indicated with black, high-usage indicated with red.)

If the temperature outise is below 18 degrees, 
increase the temperature to 21

If the temperature is above 18, 
temerature is at default