Merge pull request #5115 from TrevorDev/worldMatrixShouldntBeZero

initialize world matrix to identity instead of zero (Fixes webvr controllers)

src/babylon.node.ts

@@ -106,7 +106,7 @@
         private _children: Node[];
 
         /** @hidden */
-        public _worldMatrix = Matrix.Zero();
+        public _worldMatrix = Matrix.Identity();
         /** @hidden */
         public _worldMatrixDeterminant = 0;