Added upstream icon

Author: vimagick

README.md

@@ -3,5 +3,6 @@ docker-lantern-arm
 
 [![build](https://travis-ci.org/EasyPi/docker-lantern-arm.svg?branch=master)](https://travis-ci.org/EasyPi/docker-lantern-arm)
 [![release](https://img.shields.io/github/release/EasyPi/docker-lantern-arm.svg)](https://github.com/EasyPi/docker-lantern-arm/releases/latest)
+[![release](https://img.shields.io/github/release/getlantern/lantern.svg)](https://github.com/getlantern/lantern/releases/latest)
 
 :flashlight: Lantern for Raspberry Pi