Add Ubuntu Server distribution

Author: VirtuBox

README.md

@@ -82,6 +82,7 @@ The complete collection of (consumer) Raspberry Pi models consist of:
 - [Snappy Ubuntu Core](https://developer.ubuntu.com/core/get-started/raspberry-pi-2-3) - Official (minimal) Ubuntu distribution for IoT. ![Supports Raspberry Pi 2+](/media/badges/rpi-2+.png)
 - [TrueOS](https://www.trueos.org/handbook/pico.html) - FreeBSD-based thin client solution. ![Supports Raspberry Pi 2+](/media/badges/rpi-2+.png)
 - [Ubuntu MATE](https://ubuntu-mate.org/raspberry-pi/) - Ubuntu distribution for the Raspberry Pi based on MATE desktop. ![Supports Raspberry Pi 2+](/media/badges/rpi-2+.png)
+- [Ubuntu Server](https://www.ubuntu.com/download/iot/raspberry-pi-2-3) - Ubuntu Server distribution for the Raspberry Pi ![Supports Raspberry Pi 2+](/media/badges/rpi-2+.png) ![Supports Raspberry Pi 3](/media/badges/rpi-3.png)
 - [Volumio](https://volumio.org/) - Headless audiophile music player, designed to play music with the highest possible fidelity.
 - [Windows 10 IoT Core](https://docs.microsoft.com/nl-nl/windows/iot-core/downloads) - Windows 10 distribution for IoT. ![Supports Raspberry Pi 2+](/media/badges/rpi-2+.png)