Xiaomi MiIO Sensor: Xiaomi Air Quality Monitor (PM2.5) integration (#4780)

* Xiaomi MiIO Sensor: Xiaomi Air Quality Monitor (PM2.5) integration.

* Turn on/off service removed.

* ⬆️ Updates ha_release

source/_components/sensor.xiaomi_miio.markdown

@@ -0,0 +1,55 @@
+---
+layout: page
+title: "Xiaomi Air Quality Monitor"
+description: "Instructions how to integrate your Xiaomi Mi Air Quality Monitor within Home Assistant."
+date: 2018-02-28 08:35
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: xiaomi.png
+ha_category: Sensor
+ha_version: 0.66
+ha_iot_class: "Local Polling"
+---
+
+The `xiaomi_miio` sensor platform is observing your Xiaomi Mi Air Quality Monitor (PM2.5) and reporting the air quality index.
+
+Currently, the supported features are:
+
+* Air Quality Index (AQI)
+* Attributes
+  - power
+  - charging
+  - battery
+  - time_stat
+
+Please follow the instructions on [Retrieving the Access Token](/components/vacuum.xiaomi_miio/#retrieving-the-access-token) to get the API token.
+
+To add a Xiaomi Mi Air Quality Monitor to your installation, add the following to your `configuration.yaml` file:
+
+```yaml
+sensor:
+# Example configuration.yaml entry
+sensor:
+  - platform: xiaomi_miio
+    name: Xiaomi Air Quality Monitor
+    host: 192.168.130.73
+    token: YOUR_TOKEN
+```
+
+{% configuration %}
+host:
+  description: The IP address of your miio device.
+  required: true
+  type: string
+token:
+  description: The API token of your miio device.
+  required: true
+  type: string
+name:
+  description: The name of your miio device.
+  required: false
+  type: string
+  default: Xiaomi Miio Sensor
+{% endconfiguration %}