Generated new code and added initial data handling

BlendFile/DNA/ShapeKeyModifierData.cs

@@ -17,6 +17,9 @@ namespace BlendFile.DNA {
     public struct ShapeKeyModifierData {
         [DNAFieldAttribute(0, "ModifierData", "modifier", 120)]
         public ModifierData modifier;
+        public ShapeKeyModifierData() {
+            this.modifier = default;
+        }
         public ShapeKeyModifierData(ModifierData modifier) {
             this.modifier = modifier;
         }