Added JOY.JS (#107)

Consider the paintbrush: simple enough for a child, complex enough for an Old Master. That's what any artistic tool should strive for, and the art of programming deserves a tool that's more creative, more alive. Joy.js is a tool for making tools like that.

readme.md

@@ -148,7 +148,7 @@ Creative coding is a different discipline than programming systems. The goal is
 - [cables](https://cables.gl) [Cross-platform/Web] - Your model kit for creating beautiful interactive content. Currently in private beta, invites can be requested.
 - [Notch Builder](https://www.notch.one) [Win] - Node-based authoring tool with a strong focus on real-time graphics. Currently in beta.
 - [Synopsis](https://synopsis.video/) - A suite of open source software for computational cinematography.
-
+- [JOY.JS](https://ncase.me/joy/) - Realtime visual coding tool, easy to understand and aimed at beginners.
 ### Sound Programming Languages
 
 - [SuperCollider](http://supercollider.github.io/) [Multi-platform] - Platform for audio synthesis and algorithmic composition.