Tune dnsmasq/kubedns limits, replicas, logging

* Add dns_replicas, dns_memory/cpu_limit/requests vars for
dns related apps.
* When kube_log_level=4, log dnsmasq queries as well.
* Add log level control for skydns (part of kubedns app).
* Add limits/requests vars for dnsmasq (part of kubedns app) and
  dnsmasq daemon set.
* Drop string defaults for kube_log_level as it is int and
  is defined in the global vars as well.
* Add docs

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

roles/dnsmasq/templates/01-kube-dns.conf.j2

@@ -20,6 +20,9 @@ server=169.254.169.254
  server=8.8.4.4
 {% endif %}
 
+{% if kube_log_level == 4 %}
+log-queries
+{% endif %}
 bogus-priv
 no-resolv
 no-negcache

roles/dnsmasq/templates/dnsmasq-ds.yml

@@ -29,8 +29,11 @@ spec:
           imagePullPolicy: IfNotPresent
           resources:
             limits:
-              cpu: 100m
-              memory: 256M
+              cpu: {{ dns_cpu_limit }}
+              memory: {{ dns_memory_limit }}
+            requests:
+              cpu: {{ dns_cpu_requests }}
+              memory: {{ dns_memory_requests }}
           ports:
             - name: dns
               containerPort: 53