message: use blit instead of msgpack for user tables
diff: @@ -17,7 +17,7 @@ namespace ccfapp
  using namespace kv;
  using namespace ccf;
  - using KVMap = kv::Map<std::vector<uint8_t>, std::vector<uint8_t>>;
  + using KVMap = kv::untyped::Map;
  JSClassID kv_class_id;
  JSClassID kv_map_view_class_id;
  