Copy view matrix

plugins/babylon-with-encantar.js

         ar._camera._customViewMatrix = BABYLON.Matrix.Identity();
         ar._camera._getViewMatrix = function() { return this._customViewMatrix; };
         ar._camera.setViewMatrix = function(matrix) {
-            this._customViewMatrix = matrix;
+            this._customViewMatrix.copyFrom(matrix);
             this.getViewMatrix(true);
             this.getWorldMatrix().decompose(undefined, this._tmpQuaternion, this.position);
             BABYLON.Axis.Y.rotateByQuaternionToRef(this._tmpQuaternion, this.upVector);