temperature_usage

> room_1 = Room.create(degrees: 10)
> room_2 = Room.create(degrees: 20)
> room_3 = Room.create(degrees: 30)
> room_1.temperature.cold?
=> true
> room_1.temperature.hot?
=> false
> [room_1.temperature, Temperature.new(20), room_3.temperature, room_2.temperature].sort
=> [#<Temperature:0x007fe194378840 @degrees=10>, #<Temperature:0x007fe194378818 @degrees=20>, #<Temperature:0x007fe1943787c8 @degrees=20>, #<Temperature:0x007fe1943787f0 @degrees=30>]
> [room_1.temperature, Temperature.new(20), room_3.temperature, room_2.temperature].uniq
=> [#<Temperature:0x007fe194361e88 @degrees=10>, #<Temperature:0x007fe194361e60 @degrees=20>, #<Temperature:0x007fe194361e38 @degrees=30>]