message: Fix crash when loading JSON with uchar subtype.
diff: @@ -128,6 +128,12 @@ inline OSPSG_INTERFACE NodePtr createNodeFromJSON(const JSON &j) {
  } else {
  n = createNode(j["name"], j["subType"], j["value"].get<Any>());
  }
  +
  + // JSON doesn't distinguish between uint8_t and integer. Convert it, if
  + // the subType calls for an uchar.
  + if (j["subType"] == "uchar")
  + n->setValue(uint8_t(n->valueAs<int>()));
  +
  } else {
  n = createNode(j["name"], j["subType"]);
  }
  @@ -259,6 +265,8 @@ inline void to_json(JSON &j, const Any &a)
  j = a.get<int>();
  else if (a.is<bool>())
  j = a.get<bool>();
  + else if (a.is<uint8_t>())
  + j = a.get<uint8_t>();
  else if (a.is<float>())
  j = a.get<float>();
  else if (a.is<std::string>())
  