message: On scene file load, add transform value and not nodes.
  Adding rotation/translation/scale as nodes will keep the attached
  parent node, which is not correct.  Only update the value.
diff: @@ -241,20 +241,19 @@ OSPSG_INTERFACE void importScene(
  };
  auto importNode = findFirstChild(world, jImport.first);
  - if (importNode && jImport.second["children"][0]["subType"] == "transform") {
  + auto jNode = jImport.second["children"][0];
  + if (importNode && jNode["subType"] == "transform") {
  // should be associated xfm node
  - auto childName = jImport.second["children"][0]["name"];
  + auto childName = jNode["name"];
  Node &xfmNode = importNode->child(childName);
  - // XXX parse JSON to get RST transforms saved to sg file. This is
  - // temporary. We will want RST to be a first-class citizen node that gets
  - // handled correctly without this kind of hardcoded workaround
  - auto child = createNodeFromJSON(jImport.second["children"][0]);
  - if (child) {
  - xfmNode = child->value(); // assigns base affine3f value
  - xfmNode.add(child->child("rotation"));
  - xfmNode.add(child->child("translation"));
  - xfmNode.add(child->child("scale"));
  + auto xfm = createNodeFromJSON(jNode);
  + if (xfm) {
  + xfmNode = xfm->value(); // assigns base affine3f value
  + // Update the xfm rotation, translation and scale values
  + xfmNode["rotation"] = xfm->child("rotation").valueAs<quaternionf>();
  + xfmNode["translation"] = xfm->child("translation").valueAs<vec3f>();
  + xfmNode["scale"] = xfm->child("scale").valueAs<vec3f>();
  }
  }
  }
  