Merge pull request #23 from omise/omise-forum

Replace Gitter badge with Omise Forum

README.md

@@ -3,9 +3,9 @@ https://omg.omise.co/ instead. ⚠️**
 
 # OMISE-GO
 
-[![GoDoc](https://godoc.org/github.com/omise/omise-go?status.svg)][0] 
-[![Build Status](https://travis-ci.org/omise/omise-go.svg)](https://travis-ci.org/omise/omise-go) 
-[![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/omise/omise-go?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)
+[![GoDoc](https://godoc.org/github.com/omise/omise-go?status.svg)][0]
+[![Build Status](https://travis-ci.org/omise/omise-go.svg)](https://travis-ci.org/omise/omise-go)
+[![Omise Forum](https://img.shields.io/badge/discourse-forum-1a53f0.svg)](https://forum.omise.co)
 
 Omise is a payment service provider currently operating in Thailand. Omise provides a set
 of clean APIs that helps merchants of any size accept credit cards online.