updated what's new

dist/preview release/what's new.md

@@ -48,6 +48,7 @@
 - (Viewer) The viewer supports custom shaders in the configuration. ([RaananW](https://github.com/RaananW))
 - Documented PostProcessRenderEffect, DefaultRenderingPipeline, BlurPostProcess, DepthOfFieldEffect, PostProcess, PostProcessManager, Effect classes ([trevordev](https://github.com/trevordev))
 - SPS internal storage of each solid particle rotation matrix ([jbousquie](https://github.com/jbousquie)) 
+- SPS particle parenting feature ([jbousquie](https://github.com/jbousquie))
 - (Viewer) Introducing the viewer labs - testing new features. ([RaananW](https://github.com/RaananW))
 - AssetContainer Class and loading methods ([trevordev](https://github.com/trevordev))
 - KeepAssets class and AssetContainer.moveAllFromScene ([HoloLite](http://www.html5gamedevs.com/profile/28694-hololite/) [trevordev](https://github.com/trevordev))