Update what's new.md

dist/preview release/what's new.md

@@ -33,6 +33,9 @@
 ### Meshes
 - Added new CreateTiledPlane and CreateTiledBox ([JohnK](https://github.com/BabylonJSGuide/))
 
+### Physics
+- Update Ammo.js library to support global collision contact callbacks ([MackeyK24](https://github.com/MackeyK24/))
+
 ## Bug fixes
 - Added support for `AnimationGroup` serialization ([Drigax](https://github.com/drigax/))
 - Removing assetContainer from scene will also remove gui layers ([TrevorDev](https://github.com/TrevorDev))