Renamed datagrid and datastore packages

net.onrc.onos.datagrid.* => net.onrc.onos.core.datagrid.*
net.onrc.onos.datastore.* => net.onrc.onos.core.datastore.*

Change-Id: Ibe1894a6fabae08ea7cfcbf6595f0c91b05ef497
diff --git a/src/main/java/net/onrc/onos/core/datastore/DataStoreClient.java b/src/main/java/net/onrc/onos/core/datastore/DataStoreClient.java
new file mode 100644
index 0000000..7ec6251
--- /dev/null
+++ b/src/main/java/net/onrc/onos/core/datastore/DataStoreClient.java
@@ -0,0 +1,26 @@
+package net.onrc.onos.core.datastore;
+
+import net.onrc.onos.core.datastore.hazelcast.HZClient;
+import net.onrc.onos.core.datastore.ramcloud.RCClient;
+
+// This class probably need to be a service
+public class DataStoreClient {
+    private static final String BACKEND = System.getProperty("net.onrc.onos.core.datastore.backend", "hazelcast");
+
+    // Suppresses default constructor, ensuring non-instantiability.
+    private DataStoreClient() {}
+
+    public static IKVClient getClient() {
+        // TODO read config and return appropriate IKVClient
+        switch (BACKEND) {
+        case "ramcloud":
+            return RCClient.getClient();
+        case "hazelcast":
+            return HZClient.getClient();
+        default:
+            return HZClient.getClient();
+        }
+    }
+
+
+}