Add documentation for the Arris TG2492LG router

source/_integrations/arris_tg2492lg.markdown

@@ -0,0 +1,38 @@
+---
+title: Arris TG2492LG
+description: Instructions on how to integrate Arris TG2492LG routers into Home Assistant.
+logo: arris.jpg
+ha_category:
+  - Presence Detection
+ha_release: 0.109
+---
+
+This platform allows you to detect presence by looking at connected devices to an Arris TG2492LG router.
+
+This is one of the routers provided by [Ziggo](https://www.ziggo.nl/), a cable operator in the Netherlands, to their customers as the Ziggo Connectbox.
+
+<div class='note warning'>
+The router prevents the admin user from logging in twice. This can cause problems with accessing the router's configuration pages while this platform is active.
+</div>
+
+To use this device tracker in your installation, add the following to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+device_tracker:
+  - platform: arris_tg2492lg
+    password: YOUR_ADMIN_PASSWORD
+```
+
+{% configuration %}
+host:
+  description: The IP address of your router. The default value is `192.168.178.1`.
+  required: false
+  type: string
+password:
+  description: The password for your admin account.
+  required: true
+  type: string
+{% endconfiguration %}
+
+See the [device tracker integration page](/integrations/device_tracker/) for instructions how to configure the people to be tracked.