Deprecate joda-time

- ref:
  http://blog.joda.org/2014/11/converting-from-joda-time-to-javatime.html

Change-Id: I1115e8053f601e78cb933ccbfa664ff8787d2da1
diff --git a/core/net/src/main/java/org/onosproject/cluster/impl/ClusterManager.java b/core/net/src/main/java/org/onosproject/cluster/impl/ClusterManager.java
index fc3d802..92a3894 100644
--- a/core/net/src/main/java/org/onosproject/cluster/impl/ClusterManager.java
+++ b/core/net/src/main/java/org/onosproject/cluster/impl/ClusterManager.java
@@ -15,6 +15,7 @@
  */
 package org.onosproject.cluster.impl;
 
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -31,7 +32,6 @@
 import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.apache.felix.scr.annotations.Service;
 import org.apache.karaf.system.SystemService;
-import org.joda.time.DateTime;
 import org.onlab.packet.IpAddress;
 import org.onlab.util.Tools;
 import org.onosproject.cluster.ClusterAdminService;
@@ -147,9 +147,9 @@
     }
 
     @Override
-    public DateTime getLastUpdated(NodeId nodeId) {
+    public Instant getLastUpdatedInstant(NodeId nodeId) {
         checkPermission(CLUSTER_READ);
-        return store.getLastUpdated(nodeId);
+        return store.getLastUpdatedInstant(nodeId);
     }
 
     @Override
diff --git a/core/net/src/main/java/org/onosproject/net/device/impl/DeviceManager.java b/core/net/src/main/java/org/onosproject/net/device/impl/DeviceManager.java
index bbf6d39..eb477be 100644
--- a/core/net/src/main/java/org/onosproject/net/device/impl/DeviceManager.java
+++ b/core/net/src/main/java/org/onosproject/net/device/impl/DeviceManager.java
@@ -25,7 +25,6 @@
 import org.apache.felix.scr.annotations.Reference;
 import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.apache.felix.scr.annotations.Service;
-import org.joda.time.DateTime;
 import org.onlab.util.KryoNamespace;
 import org.onlab.util.Tools;
 import org.onosproject.cluster.ClusterService;
@@ -74,6 +73,7 @@
 import org.onosproject.store.service.Serializer;
 import org.slf4j.Logger;
 
+import java.time.Instant;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.List;
@@ -180,9 +180,9 @@
      */
     private class LocalStatus {
         boolean connected;
-        DateTime dateTime;
+        Instant dateTime;
 
-        public LocalStatus(boolean b, DateTime now) {
+        public LocalStatus(boolean b, Instant now) {
             connected = b;
             dateTime = now;
         }
@@ -333,7 +333,7 @@
         if (ls == null) {
             return "No Record";
         }
-        String timeAgo = Tools.timeAgo(ls.dateTime.getMillis());
+        String timeAgo = Tools.timeAgo(ls.dateTime.toEpochMilli());
         return (ls.connected) ? "connected " + timeAgo : "disconnected " + timeAgo;
     }
 
@@ -508,7 +508,7 @@
             checkNotNull(deviceDescription, DEVICE_DESCRIPTION_NULL);
             checkValidity();
 
-            deviceLocalStatus.put(deviceId, new LocalStatus(true, DateTime.now()));
+            deviceLocalStatus.put(deviceId, new LocalStatus(true, Instant.now()));
 
             BasicDeviceConfig cfg = networkConfigService.getConfig(deviceId, BasicDeviceConfig.class);
             if (!isAllowed(cfg)) {
@@ -564,7 +564,7 @@
         public void deviceDisconnected(DeviceId deviceId) {
             checkNotNull(deviceId, DEVICE_ID_NULL);
             checkValidity();
-            deviceLocalStatus.put(deviceId, new LocalStatus(false, DateTime.now()));
+            deviceLocalStatus.put(deviceId, new LocalStatus(false, Instant.now()));
             log.info("Device {} disconnected from this node", deviceId);
 
             List<PortDescription> descs = store.getPortDescriptions(provider().id(), deviceId)