Added initial zhimi.humidifier.ca6 support (#1885)

Adds support for zhimi.humidifier.ca6 and status container descriptors
for airhumidifier_miot.

Author: smmoroz

miio/__init__.py

@@ -90,7 +90,11 @@
 from miio.integrations.zhimi.airpurifier import AirFresh, AirPurifier, AirPurifierMiot
 from miio.integrations.zhimi.fan import Fan, FanZA5
 from miio.integrations.zhimi.heater import Heater, HeaterMiot
-from miio.integrations.zhimi.humidifier import AirHumidifier, AirHumidifierMiot
+from miio.integrations.zhimi.humidifier import (
+    AirHumidifier,
+    AirHumidifierMiot,
+    AirHumidifierMiotCA6,
+)
 from miio.integrations.zimi.powerstrip import PowerStrip
 from miio.protocol import Message, Utils
 from miio.push_server import EventInfo, PushServer

miio/integrations/zhimi/humidifier/__init__.py

@@ -1,3 +1,3 @@
 # flake8: noqa
 from .airhumidifier import AirHumidifier
-from .airhumidifier_miot import AirHumidifierMiot
+from .airhumidifier_miot import AirHumidifierMiot, AirHumidifierMiotCA6