allow to pass options to dnsmasq service

There were request to pass parameters to dnsmasq container in kube-dns
addon.

This PR adds variable master.addons.dns.dnsmasq (dict) which can be
used to pass options to dnsmasq container. Defaults are configured in
metadata.

Change-Id: If072e31a8a1cde4c984c67373ad74d45204619b0

kubernetes/files/kube-addons/dns/skydns-rc.yaml

@@ -71,10 +71,11 @@ spec:
           successThreshold: 1
           failureThreshold: 5
         args:
-        - --cache-size=1000
-        - --no-resolv
-        - --server=127.0.0.1#10053
-        - --log-facility=-
+{%- if master.addons.dns.get('dnsmasq', {}) %}
+{%- for option_name, option_value in master.addons.dns.dnsmasq.iteritems() %}
+        - --{{ option_name }}{% if option_value %}={{ option_value }}{% endif %}
+{%- endfor %}
+{%- endif %}
         ports:
         - containerPort: 53
           name: dns
@@ -100,4 +101,4 @@ spec:
         ports:
         - containerPort: 8080
           protocol: TCP
-      dnsPolicy: Default  # Don't use cluster DNS.
+      dnsPolicy: Default  # Don't use cluster DNS.

metadata/service/master/cluster.yml

@@ -32,6 +32,11 @@ parameters:
           replicas: 1
           domain: cluster.local
           server: 10.254.0.10
+          dnsmasq:
+            cache-size: 1000
+            no-resolv:
+            server: 127.0.0.1#10053
+            log-facility: "-"
         dashboard:
           enabled: True
         heapster_influxdb:

metadata/service/master/single.yml

@@ -28,6 +28,11 @@ parameters:
           replicas: 1
           domain: cluster.local
           server: 10.254.0.10
+          dnsmasq:
+            cache-size: 1000
+            no-resolv:
+            server: 127.0.0.1#10053
+            log-facility: "-"
         dashboard:
           enabled: True
         heapster_influxdb: