Link to new 2D Toolkit website.

spine-tk2d/README.md

@@ -1,3 +1,3 @@
 # spine-tk2d
 
-The spine-tk2d runtime has been merged into [spine-unity](https://github.com/EsotericSoftware/spine-runtimes/tree/master/spine-unity). You may use spine-unity with [2D Toolkit](http://www.unikronsoftware.com/2dtoolkit/).
+The spine-tk2d runtime has been merged into [spine-unity](https://github.com/EsotericSoftware/spine-runtimes/tree/master/spine-unity). You may use spine-unity with [2D Toolkit](http://www.2dtoolkit.com/).