gRPC migration update

Change-Id: Icdd1a824948fa994cd36bd121c962f5ecf74e3cf
diff --git a/vendor/github.com/rcrowley/go-metrics/.travis.yml b/vendor/github.com/rcrowley/go-metrics/.travis.yml
index aead076..ce9afea 100644
--- a/vendor/github.com/rcrowley/go-metrics/.travis.yml
+++ b/vendor/github.com/rcrowley/go-metrics/.travis.yml
@@ -11,6 +11,9 @@
     - "1.10"
     - "1.11"
     - "1.12"
+    - "1.13"
+    - "1.14"
+    - "1.15"
 
 script:
     - ./validate.sh