[VOL-1435] Initial submission for device management integration
tests.  This update also comprises of some fixes with kafka
consumer and random mac address generation.

Change-Id: I4f8081752af646c3ed218ab17a541abb1b70cf5c
diff --git a/kafka/client.go b/kafka/client.go
index 8cc1999..316a4a5 100644
--- a/kafka/client.go
+++ b/kafka/client.go
@@ -26,7 +26,13 @@
 )
 
 const (
+	OffsetNewest = -1
+	OffsetOldest = -2
+)
+
+const (
 	GroupIdKey = "groupId"
+	Offset = "offset"
 )
 
 const (