VOL-1381 and VOL-1091 Add feature to collect PMmetrics of OLT, this will collect Tx and Rx and posts to kafka. This commit is also related to changes of commit 72b25abd4e804596413558ef10f098c2262dd65d voltha-go
Updated review comments

Updated with code optimization
Updated with dep files
Updated fix for sanity test
Updated with gomod changes

Change-Id: I899e855812a6eda812c64664a9154321cdb16876
diff --git a/mocks/mockEventproxy.go b/mocks/mockEventproxy.go
index be3049a..86479df 100644
--- a/mocks/mockEventproxy.go
+++ b/mocks/mockEventproxy.go
@@ -35,3 +35,12 @@
 	}
 	return nil
 }
+
+// SendKpiEvent mocks the SendKpiEvent function
+func (me *MockEventProxy) SendKpiEvent(id string, deviceEvent *voltha.KpiEvent2, category voltha.EventCategory_EventCategory,
+	subCategory voltha.EventSubCategory_EventSubCategory, raisedTs int64) error {
+	if raisedTs == 0 {
+		return errors.New("raisedTS cannot be zero")
+	}
+	return nil
+}