Update AtomicValue test CLI

- Add missing command
- Add error message for unknown command
- In support of [ONOS-2451]

Change-Id: Iaeb91e43272c7f0f468f9d3a201a4f8b2ae629d5
diff --git a/apps/test/distributed-primitives/src/main/java/org/onosproject/distributedprimitives/cli/ValueTestCommand.java b/apps/test/distributed-primitives/src/main/java/org/onosproject/distributedprimitives/cli/ValueTestCommand.java
index fb736eb..aa17ca4 100644
--- a/apps/test/distributed-primitives/src/main/java/org/onosproject/distributedprimitives/cli/ValueTestCommand.java
+++ b/apps/test/distributed-primitives/src/main/java/org/onosproject/distributedprimitives/cli/ValueTestCommand.java
@@ -66,8 +66,12 @@
             atomicValue.set(value1);
         } else if (operation.equals("compareAndSet")) {
             print("%b", atomicValue.compareAndSet(value1, value2));
+        } else if (operation.equals("getAndSet")) {
+            print("%s", atomicValue.getAndSet(value1));
         } else if (operation.equals("destroy")) {
             atomicValue.destroy();
+        } else {
+            print("Error, unknown operation %s", operation);
         }
     }
 }