Updated README.

README.md

@@ -6,7 +6,7 @@ Image library.
 [![Build Status](https://travis-ci.org/bkaradzic/bx.svg?branch=master)](https://travis-ci.org/bkaradzic/bimg)
 [![Build status](https://ci.appveyor.com/api/projects/status/edras3mltmoy31g5?svg=true)](https://ci.appveyor.com/project/bkaradzic/bimg)
 [![License](https://img.shields.io/badge/license-BSD--2%20clause-blue.svg)](https://bkaradzic.github.io/bgfx/license.html)
-[![Join the chat at https://gitter.im/bkaradzic/bgfx](https://badges.gitter.im/bkaradzic/bgfx.svg)](https://gitter.im/bkaradzic/bgfx)
+[![Join the chat at https://discord.gg/9eMbv7J](https://img.shields.io/discord/712512073522872352?color=%237289DA&label=bimg&logo=discord&logoColor=white)](https://discord.gg/9eMbv7J)
 
 Contact
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