Re-organisation Documentation and Getting started (#2055)

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source/_docs/mqtt/birth_will.markdown

@@ -0,0 +1,40 @@
+---
+layout: page
+title: "MQTT Birth and Last will"
+description: "Instructions how to setup MQTT birth and last will messages within Home Assistant."
+date: 2015-08-07 18:00
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: mqtt.png
+---
+
+MQTT support so-called Birth and Last Will and Testament (LWT) messages. The former is used to sned a message after the service has started. the latter is here to notify other clients about an ungracefully disconnected client or alike.
+
+To integrate MQTT Birth and Last Will messages into Home Assistant, add the following section to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+mqtt:
+  birth_message:
+    topic: 'hass/status'
+    payload: 'online'
+  will_message:
+    topic: 'hass/status'
+    payload: 'offline'
+```
+
+Configuration variables:
+
+- **birth_message** (*Optional*):
+  - **topic** (*Required*): The MQTT topic to publish the message.
+  - **payload** (*Required*): The message content.
+  - **qos** (*Optional*): The maximum QoS level of the topic. Default is 0.
+  - **retain** (*Optional*): If the published message should have the retain flag on or not. Defaults to `True`.
+- **will_message** (*Optional*):
+  - **topic** (*Required*): The MQTT topic to publish the message.
+  - **payload** (*Required*): The message content.
+  - **qos** (*Optional*): The maximum QoS level of the topic. Default is 0.
+  - **retain** (*Optional*): If the published message should have the retain flag on or not. Defaults to `True`.
+