Replication Lag parameter in diagnostics

Replication Lag parameter value is now printed in diagnostics routine
for MySQL monitor

server/modules/monitor/mysql_mon.c

@@ -271,6 +271,7 @@ char		*sep;
 
 	dcb_printf(dcb,"\tSampling interval:\t%lu milliseconds\n", handle->interval);
 	dcb_printf(dcb,"\tMaxScale MonitorId:\t%lu\n", handle->id);
+	dcb_printf(dcb,"\tReplication lag check:\t%s\n", (handle->replicationHeartbeat == 1) ? "enabled" : "disabled");
 	dcb_printf(dcb, "\tMonitored servers:	");
 
 	db = handle->databases;