readme: update

Author: dg

readme.md

@@ -6,7 +6,6 @@
 [![Build Status Windows](https://ci.appveyor.com/api/projects/status/github/nette/tracy?branch=master&svg=true)](https://ci.appveyor.com/project/dg/tracy/branch/master)
 [![Latest Stable Version](https://poser.pugx.org/tracy/tracy/v/stable)](https://github.com/nette/tracy/releases)
 [![License](https://img.shields.io/badge/license-New%20BSD-blue.svg)](https://github.com/nette/tracy/blob/master/license.md)
-[![Join the chat at https://gitter.im/nette/tracy](https://badges.gitter.im/nette/tracy.svg)](https://gitter.im/nette/tracy)
 
 
 Introduction