[WIP] Upgrade ONOS to karaf version 4.2.1

Change-Id: I7cd40c995bdf1c80f94b1895fb3344e32404c7fa
diff --git a/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java b/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java
index 35dedbd..2f6ba52 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java
@@ -17,13 +17,6 @@
 
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
-
-import org.apache.felix.scr.annotations.Activate;
-import org.apache.felix.scr.annotations.Component;
-import org.apache.felix.scr.annotations.Deactivate;
-import org.apache.felix.scr.annotations.Reference;
-import org.apache.felix.scr.annotations.ReferenceCardinality;
-import org.apache.felix.scr.annotations.Service;
 import org.onlab.packet.IpAddress;
 import org.onlab.packet.MacAddress;
 import org.onlab.packet.VlanId;
@@ -44,12 +37,17 @@
 import org.onosproject.store.AbstractStore;
 import org.onosproject.store.serializers.KryoNamespaces;
 import org.onosproject.store.service.ConsistentMap;
+import org.onosproject.store.service.DistributedPrimitive.Status;
 import org.onosproject.store.service.MapEvent;
 import org.onosproject.store.service.MapEventListener;
 import org.onosproject.store.service.Serializer;
 import org.onosproject.store.service.StorageService;
-import org.onosproject.store.service.DistributedPrimitive.Status;
 import org.onosproject.store.service.Versioned;
+import org.osgi.service.component.annotations.Activate;
+import org.osgi.service.component.annotations.Component;
+import org.osgi.service.component.annotations.Deactivate;
+import org.osgi.service.component.annotations.Reference;
+import org.osgi.service.component.annotations.ReferenceCardinality;
 import org.slf4j.Logger;
 
 import java.util.Collection;
@@ -69,21 +67,23 @@
 import static java.util.concurrent.Executors.newSingleThreadScheduledExecutor;
 import static org.onlab.util.Tools.groupedThreads;
 import static org.onosproject.net.DefaultAnnotations.merge;
-import static org.onosproject.net.host.HostEvent.Type.*;
+import static org.onosproject.net.host.HostEvent.Type.HOST_ADDED;
+import static org.onosproject.net.host.HostEvent.Type.HOST_MOVED;
+import static org.onosproject.net.host.HostEvent.Type.HOST_REMOVED;
+import static org.onosproject.net.host.HostEvent.Type.HOST_UPDATED;
 import static org.slf4j.LoggerFactory.getLogger;
 
 /**
  * Manages the inventory of hosts using a {@code EventuallyConsistentMap}.
  */
-@Component(immediate = true)
-@Service
+@Component(immediate = true, service = HostStore.class)
 public class DistributedHostStore
     extends AbstractStore<HostEvent, HostStoreDelegate>
     implements HostStore {
 
     private final Logger log = getLogger(getClass());
 
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
     protected StorageService storageService;
 
     private ConsistentMap<HostId, DefaultHost> hostsConsistentMap;