update whats new

dist/preview release/what's new.md

@@ -41,7 +41,7 @@
 - Gulp process now supports multiple outputs when using webpack. ([RaananW](https://github.com/RaananW))
 - (Viewer) Scene Optimizer intergrated in viewer. ([RaananW](https://github.com/RaananW))
 - (Viewer) The viewer supports custom shaders in the configuration. ([RaananW](https://github.com/RaananW))
-- Documented PostProcessRenderEffect, DefaultRenderingPipeline, BlurPostProcess, DepthOfFieldEffect, PostProcess, PostProcessManager classes ([trevordev](https://github.com/trevordev))
+- 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)) 
 - (Viewer) Introducing the viewer labs - testing new features. ([RaananW](https://github.com/RaananW))