Update documentation

Author: AndreyAkinshin

README.md

@@ -8,7 +8,7 @@
 
   [![NuGet](https://img.shields.io/nuget/v/BenchmarkDotNet.svg)](https://www.nuget.org/packages/BenchmarkDotNet/)
   [![Downloads](https://img.shields.io/nuget/dt/benchmarkdotnet.svg)](https://www.nuget.org/packages/BenchmarkDotNet/)
-  ![Stars](https://img.shields.io/github/stars/dotnet/BenchmarkDotNet?color=brightgreen)
+  [![Stars](https://img.shields.io/github/stars/dotnet/BenchmarkDotNet?color=brightgreen)](https://github.com/dotnet/BenchmarkDotNet/stargazers)
   [![Gitter](https://img.shields.io/gitter/room/dotnet/BenchmarkDotNet?color=yellow)](https://gitter.im/dotnet/BenchmarkDotNet)
   [![License](https://img.shields.io/badge/license-MIT-blue.svg)](LICENSE.md)