Refactoring datastore package

Preparation to make datastore replacable
- Extract datastore interfaces
- Add multi Read/Write/Remove
- Add a method to walk over RCTable
- Refactor serialize/deserialize RCObject
- Localize dependency to JRAMCloud
  - Separate RAMCloud specific code into ramcloud package
  - Remove dependency to RAMCloud exception classes
  - Remove RC prefix from non RAMCloud specific code
- Cosmetics and update sample/test code

- reflect Naoki's comment
- more cosmetic fixes
  - reordered OPERATION enums

- removed no longer used code
- follow pmd, etc. where easily possible

Change-Id: I6f9153d705600447acf48a64f713c654c9f26713
diff --git a/src/main/java/net/onrc/onos/datastore/DataStoreClient.java b/src/main/java/net/onrc/onos/datastore/DataStoreClient.java
new file mode 100644
index 0000000..88daa8e
--- /dev/null
+++ b/src/main/java/net/onrc/onos/datastore/DataStoreClient.java
@@ -0,0 +1,10 @@
+package net.onrc.onos.datastore;
+
+import net.onrc.onos.datastore.ramcloud.RCClient;
+
+public class DataStoreClient {
+    public static IKVClient getClient() {
+	// TODO read config and return appropriate IKVClient
+	return RCClient.getClient();
+    }
+}