Added select() backend which can be used as a fallback if epoll is not available.

src/core/hub.h

@@ -91,10 +91,6 @@ struct hub_logout_info
 struct hub_info
 {
 	struct net_connection* server;
-#ifdef USE_LIBEVENT
-	struct event ev_accept;
-	struct event ev_timer;
-#endif
 	struct hub_stats stats;
 	struct event_queue* queue;
 	struct hub_config* config;