Air Purifier Pro: support for sound volume level and fix for bright propery

[yawor]

The Air Purifier Pro has a property controlling the volume level of sound notifications, which are used when any command is sent to it. I've added support for the property and a method to set it's value. The range is from 0 (mute) to 100 (full volume). I don't know if Air Purifier 2 also has this property or not.

There's a photosensitive element on top of the Air Purifier Pro (right next to the power/mode selection button). It's value is held in the bright property, which has been improperly used as a LED brightness for this model. Air Purifier Pro display probably doesn't support changing brightness. The value for the bright property changes from 0 (no light detected) up to 200. I don't know what's the unit it is given in. I've got 200 when I've used my phone's LED flashlight directly on the sensor.

[coveralls]

Coverage increased (+0.007%) to 63.088% when pulling 1637818 on yawor:air_purifier_pro_fixes into dd76fcd on rytilahti:master.

[yawor]

OK, I've tested the bright value against another illuminance sensor and the value seems to be in lux. The value is not equal to the other sensor, but there's a difference of about 3 lx - probably because of where the sensor is located and gets slightly less light than the other one.

[coveralls]

Coverage increased (+0.007%) to 63.088% when pulling 0031522 on yawor:air_purifier_pro_fixes into dd76fcd on rytilahti:master.

[yawor]

I've changed the name of the brightness property to illuminance. It's more appropriate regarding it's function. For example in the Home Assistant, illuminance is a type of sensor providing information about the amount of light.

[rytilahti]

This looks fine for me to be merged, however I cannot test it myself. @syssi what's your opinion on this?

edit: to add, @yawor, could you mention your findings wrt illuminance in code comments too?

[syssi]

Looks good! 👍

[yawor]

@rytilahti can you point me to where's the best place to add that information in the code?

[rytilahti]

@yawor I'd say directly into the docstring of the method, simply by adding "reported in lux, values between [0-200]" or similar would do fine. The point is just to make it somewhat visible for anyone stumbling upon that code / trying to use it in their own code.

[coveralls]

Coverage increased (+0.007%) to 63.088% when pulling 313cfad on yawor:air_purifier_pro_fixes into dd76fcd on rytilahti:master.

[rytilahti]

Looks great, thanks!