Fix #29 limiting SHM updates to 1 per second

src/responder.c

 	short idle, busy;
 	struct sigaction act;
 	char *statusstr;
+	time_t last_update, now;
 
 	act.sa_handler = pool_sighandler;
 	sigemptyset(&act.sa_mask);
 	//Wait at least for a process to be ready
 	while(!pyfcgi_pool_idle(&timeout));
 
+	last_update = 0;
+
 	// main loop, taking care to restart terminated workers, 
 	// spawn new one if needed, etc.
 	while(1)
 	{
 		pyfcgi_wd_arm();
 		PyFCGI_conf.context.n_wrk = n_wrk;
-		pyfcgi_pool_shm_update(n_wrk);
+		if(last_update != (now = time(NULL)))
+		{
+			pyfcgi_pool_shm_update(n_wrk);
+			last_update = now;
+		}
 		if( (ret = waitpid(0, &status, WNOHANG)) )
 		{
 			if(ret < 0)
 	exit(PYFCGI_TIMEOUT);
 }
 
-
 void pyfcgi_pool_shm_update(int nworker)
 {
 	short retry;