Pass plugin type when calling the host application

src/wine-host/bridges/vst2.h

@@ -66,6 +66,9 @@ class Vst2Bridge {
      *
      * @throw std::runtime_error Thrown when the VST plugin could not be loaded,
      *   or if communication could not be set up.
+     *
+     * TODO: Make these two arguments `boost::filesystem::path`, also use those
+     *       in `GroupRequest`.
      */
     Vst2Bridge(MainContext& main_context,
                std::string plugin_dll_path,