libreactor: listen to the correct address (#3240)

frameworks/C/libreactor/src/main.c

@@ -134,7 +134,7 @@ int main()
   setup(1, 0);  
   (void) reactor_core_construct();
   (void) reactor_timer_open(&timer, timer_event, &timer, 1, 1000000000);
-  (void) reactor_tcp_open(&tcp, tcp_event, &tcp, "127.0.0.1", "8080", REACTOR_TCP_FLAG_SERVER);
+  (void) reactor_tcp_open(&tcp, tcp_event, &tcp, "0.0.0.0", "8080", REACTOR_TCP_FLAG_SERVER);
   (void) reactor_core_run();
   reactor_core_destruct();
 }