Update README.md

Author: elect86

README.md

@@ -4,6 +4,7 @@
 [![license](https://img.shields.io/badge/License-MIT-orange.svg)](https://github.com/kotlin-graphics/kotlin-unsigned/blob/master/LICENSE) 
 ![](https://reposs.herokuapp.com/?path=kotlin-graphics/kotlin-unsigned&color=yellow) 
 [![Release](https://jitpack.io/v/kotlin-graphics/kotlin-unsigned.svg)](https://jitpack.io/#kotlin-graphics/kotlin-unsigned) 
+[![Github All Releases](https://img.shields.io/github/downloads/kotlin-graphics/kotlin-unsigned/total.svg)]()
 [![Slack Status](http://slack.kotlinlang.org/badge.svg)](http://slack.kotlinlang.org/)
 
 Unsigned operators and boxed types (`Ubyte`, `Uint`, `Ulong` and `Ushort`) for unsigned support.