VOL-3938 - support custom configuration to etcdclient

also enables grpc reflection to the voltha grpc api

Change-Id: Ib7f6d214e5fcd1decd4ef875e03a31e3319555e2
diff --git a/vendor/modules.txt b/vendor/modules.txt
index bbe6bd0..7b1ab23 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -306,6 +306,8 @@
 google.golang.org/grpc/metadata
 google.golang.org/grpc/naming
 google.golang.org/grpc/peer
+google.golang.org/grpc/reflection
+google.golang.org/grpc/reflection/grpc_reflection_v1alpha
 google.golang.org/grpc/resolver
 google.golang.org/grpc/resolver/dns
 google.golang.org/grpc/resolver/passthrough