Add Korean community

Author: ragingwind

README.md

@@ -69,6 +69,7 @@ forums
 - `#atom-shell` channel on Freenode
 - [`Atom`](http://atom-slack.herokuapp.com/) channel on Slack
 - [`electron-br`](https://electron-br.slack.com) *(Brazilian Portuguese)*
+- [`electron-kr`](http://www.meetup.com/electron-kr/) *(Korean)*
 
 Check out [awesome-electron](https://github.com/sindresorhus/awesome-electron)
 for a community maintained list of useful example apps, tools and resources.