Adding the ability of soft shutdown, restart and reset ui to lakka on Raspberry Pi 3

1. Make sure the raspberry pi is connected to the internet.

2. Make sure SSH is enabled in Lakka (Config / Services / SSH Enable is ON).

3. ssh into lakka:

   ssh root@YOUR_LAKKA_IP_ADDRESS
   password: root (if unchanged)

4. In the terminal, type the one-line command below(Case sensitive):

   wget -O - "https://github.com/edus44/lakka-gpio-control/raw/master/install.sh" | bash

5. Your Raspberry Pi will reboot and you're done!