Document UNRAID App installation (#30)

Author: sebastienvermeille

docs/getting-started/install/installation-guide-unraid.md

@@ -0,0 +1,40 @@
+---
+title: UNRAID App
+sidebar_position: 2
+---
+import CenteredImage from '@site/src/components/CenteredImage';
+import Tabs from '@theme/Tabs';
+import TabItem from '@theme/TabItem';
+
+# UNRAID App
+
+:::info
+In order to have access to the NSPanel Manager UNRAID App
+you first have to [install the Community Apps plugin](https://unraid.net/community/apps).
+:::
+
+## Installation
+
+Like for any other UNRAID App, simply login to your UNRAID user interface and click on **APPS** link.
+
+Search for NSPanelManager in Home Automation category and you will find:
+
+<CenteredImage
+src="/images/doc/unraid/unraid-app-preview.png"
+alt="NSPanel Manager UNRAID App preview"
+figureNumber={1}
+/>
+
+Then click on **Actions** and select  **Install**:
+
+<CenteredImage
+src="/images/doc/unraid/unraid-app-install-context-menu.png"
+alt="Context menu"
+figureNumber={2}
+/>
+
+Then configure your app as desired (port and data directory)
+
+## After installation is complete
+
+You can now [configure NSPanelManager](./../configuration).