Rename L2 load balancer to port load balancer

CLI commands are also renamed to plbs, plb-add and plb-remove

Change-Id: I4c26b390acc5a961594a1dca92a76bee2148c090
diff --git a/apps/segmentrouting/BUILD b/apps/segmentrouting/BUILD
index d3846f3..1304a5e 100644
--- a/apps/segmentrouting/BUILD
+++ b/apps/segmentrouting/BUILD
@@ -10,7 +10,7 @@
     required_apps = [
         "org.onosproject.route-service",
         "org.onosproject.mcast",
-        "org.onosproject.l2lb",
+        "org.onosproject.portloadbalancer",
     ],
     title = "Segment Routing",
     url = "http://onosproject.org",