Added local_ip integration (#11466)

* Added localip component

* Apply suggestions from code review

Co-Authored-By: Klaas Schoute <klaas_schoute@hotmail.com>

* ✏️ Tweak

* Rename localip to local_ip.  Add config entry

* Update release and description

Co-authored-by: Klaas Schoute <klaas_schoute@hotmail.com>
Co-authored-by: Franck Nijhof <frenck@frenck.nl>
Co-authored-by: Fabian Affolter <mail@fabian-affolter.ch>

source/_integrations/local_ip.markdown

@@ -0,0 +1,28 @@
+---
+title: "Local IP Address"
+description: "Instructions on how to integrate the Local IP Address sensor into Home Assistant."
+logo: home-assistant.png
+ha_category:
+  - Network
+ha_iot_class: Local Polling
+ha_release: 0.105
+---
+
+The `local_ip` sensor will expose the local (LAN) IP address of your Home Assistant instance. This can be useful when your instance has a static public hostname (for example, if you use the Nabu Casa service), but have a dynamically allocated local LAN address (for example, configured via DHCP).
+
+The sensor can be added via the user interface or using the `configuration.yaml` file. To enable this sensor, via the `configuration.yaml` file, add the following minimal configuration:
+
+```yaml
+# Example configuration.yaml entry
+local_ip:
+```
+
+To configure via the user interface, select the `Local IP Address` integration.
+
+{% configuration %}
+name:
+  description: Friendly name of the sensor.
+  required: false
+  type: string
+  default: local_ip
+{% endconfiguration %}