Free glog and gflags before quit, to make leak detection easier

example_simple.cc

@@ -17,4 +17,7 @@ int main(int argc, char *argv[]) {
 	}, FLAGS_threads);
 	server.RegisterSignalHandlers();
 	server.Serve();
+
+	gflags::ShutDownCommandLineFlags();
+	google::ShutdownGoogleLogging();
 }