add IRC info to readme

README.md

@@ -11,6 +11,10 @@ Image manipulation is done by [lwip](https://github.com/EyalAr/lwip)
 
 See the [API Usage](https://crafatar.com)
 
+## Contact
+
+You can [join us](https://webchat.esper.net/?channels=spongy) in #spongy on irc.esper.net.
+
 ## Install
 
 * Clone the repository