LeadershipService API change: Using NodeId in place of ControllerNode.

Change-Id: I6f688506c3672977456fc6921b26e98be2239632
diff --git a/cli/src/main/java/org/onlab/onos/cli/net/LeaderCommand.java b/cli/src/main/java/org/onlab/onos/cli/net/LeaderCommand.java
index 7ea3ebb..ec99614 100644
--- a/cli/src/main/java/org/onlab/onos/cli/net/LeaderCommand.java
+++ b/cli/src/main/java/org/onlab/onos/cli/net/LeaderCommand.java
@@ -37,7 +37,7 @@
         Map<String, Leadership> leaderBoard = leaderService.getLeaderBoard();
         print(FMT, "Topic", "Leader");
         for (String topic : leaderBoard.keySet()) {
-            print(FMT, topic, leaderBoard.get(topic).leader().id());
+            print(FMT, topic, leaderBoard.get(topic).leader());
         }
     }