[VOL-4292] OpenOLT Adapter changes for gRPC migration

Change-Id: I5af2125f2c2f53ffc78c474a94314bba408f8bae
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