Add documentation for homekit controller component (#4966)

* Add documentation for homekit controller component

* Update docs to match the implementation

* ⬆️ ha_release

* ✏️ Language tweak

* ⬆️ ha_release

* ⬆️ ha_release

source/_components/discovery.markdown

@@ -23,6 +23,7 @@ Home Assistant can discover and automatically configure [zeroconf](https://en.wi
  * [DirecTV receivers](/components/media_player.directv/)
  * [Frontier Silicon internet radios](/components/media_player.frontier_silicon/)
  * [Google Cast](/components/media_player.cast/)
+ * [HomeKit](/components/homekit_controller/)
  * [IKEA Trådfri (Tradfri)](/components/tradfri/)
  * [Linn / Openhome](/components/media_player.openhome/)
  * [Logitech Harmony Hub](/components/remote.harmony/)
@@ -50,6 +51,8 @@ discovery:
   ignore:
     - sonos
     - samsung_tv
+  enable:
+    - homekit
 ```
 
 Configuration variables:
@@ -85,6 +88,12 @@ Valid values for ignore are:
  * `yamaha`: Yamaha media player
  * `yeelight`: Yeelight Sunflower bulb
 
+- **enable** (*Optional*): A list of platforms not enabled by default that `discovery` should discover.
+
+Valid values for enable are:
+
+ * `homekit`: HomeKit accessories
+
 <p class='note'>
 Home Assistant must be on the same network as the devices for uPnP discovery to work.
 If running Home Assistant in a [Docker container](/docs/installation/docker/) use switch `--net=host` to put it on the host's network.

source/_components/homekit_controller.markdown

@@ -0,0 +1,31 @@
+---
+layout: page
+title: "HomeKit controller support"
+description: "Instructions how to integrate your HomeKit devices within Home Assistant."
+date: 2018-03-19 21:04
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: apple-homekit.png
+ha_category: Hub
+ha_release: 0.68
+ha_iot_class: "Local Polling"
+---
+
+[HomeKit](https://developer.apple.com/homekit/) controller integration for Home Assistant allows you to connect HomeKit accessories to Home Assistant. This component should not be confused with the [HomeKit](homekit) component, which allows you to control Home Assistant devices via HomeKit.
+
+There is currently support for the following device types within Home Assistant:
+
+- [Light](../light.homekit_controller)
+- [Switch](../switch.homekit_controller)
+
+The component will be automatically configured if the [`discovery:`](components/discovery/) component is enabled and an enable entry added for HomeKit:
+
+```yaml
+discovery:
+  enable:
+    - homekit
+```
+
+For each detected HomeKit accessory, a configuration prompt will appear in the web front end. Use this to provide the HomeKit PIN.

source/_components/light.homekit_controller.markdown

@@ -0,0 +1,16 @@
+---
+layout: page
+title: "HomeKit Light"
+description: "Instructions how to setup HomeKit lights within Home Assistant."
+date: 2017-03-19 21:08
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: apple-homekit.png
+ha_category: Light
+ha_iot_class: "Local Polling"
+ha_release: 0.68
+---
+
+To get your HomeKit lights working with Home Assistant, follow the instructions for the general [HomeKit controller component](/components/homekit_controller/).

source/_components/switch.homekit_controller.markdown

@@ -0,0 +1,16 @@
+---
+layout: page
+title: "HomeKit Light"
+description: "Instructions how to setup HomeKit switches within Home Assistant."
+date: 2017-03-19 21:08
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: apple-homekit.png
+ha_category: Light
+ha_iot_class: "Local Polling"
+ha_release: 0.68
+---
+
+To get your HomeKit switches working with Home Assistant, follow the instructions for the general [HomeKit controller component](/components/homekit_controller/).