add horizontal DNS autoscaler

Change-Id: I199bf205cb2a3a3436b8e395098f27725dc75d05
diff --git a/metadata/service/master/cluster.yml b/metadata/service/master/cluster.yml
index 6663bf2..70ea012 100644
--- a/metadata/service/master/cluster.yml
+++ b/metadata/service/master/cluster.yml
@@ -30,6 +30,7 @@
         dns:
           enabled: true
           replicas: 1
+          autoscaler: True
           domain: cluster.local
           server: 10.254.0.10
           dnsmasq:
diff --git a/metadata/service/master/single.yml b/metadata/service/master/single.yml
index 172f009..3ceebf6 100644
--- a/metadata/service/master/single.yml
+++ b/metadata/service/master/single.yml
@@ -26,6 +26,7 @@
         dns:
           enabled: true
           replicas: 1
+          autoscaler: True
           domain: cluster.local
           server: 10.254.0.10
           dnsmasq: