Remove Master/Slave terminology from stateless application tutorial.

The stateless application tutorial is littered with unsuitable terminology. This update switches the database technology to a database that has already updated their own terminology as well as removes the terminology from the tutorial itself.

The advanced logging tutorial followup is set to Draft as it will take a larger effort to convert that, and I'm not convinced its even in a working state right now.

A followup PR to the examples repo to be referenced here will be made.

Addresses #22918

Signed-off-by: Paul Czarkowski <username.taken@gmail.com>

address comments in PR

Signed-off-by: Paul Czarkowski <username.taken@gmail.com>

remove confusing comment about dns, we can assume k8s has kube-dns

Signed-off-by: Paul Czarkowski <username.taken@gmail.com>

content/en/examples/application/guestbook/frontend-deployment.yaml

@@ -3,22 +3,24 @@ kind: Deployment
 metadata:
   name: frontend
   labels:
-    app: guestbook
+    app.kubernetes.io/name: guestbook
+    app.kubernetes.io/component: frontend
 spec:
   selector:
     matchLabels:
-      app: guestbook
-      tier: frontend
+      app.kubernetes.io/name: guestbook
+      app.kubernetes.io/component: frontend
   replicas: 3
   template:
     metadata:
       labels:
-        app: guestbook
-        tier: frontend
+        app.kubernetes.io/name: guestbook
+        app.kubernetes.io/component: frontend
     spec:
       containers:
-      - name: php-redis
-        image: gcr.io/google-samples/gb-frontend:v4
+      - name: guestbook
+        image: paulczar/gb-frontend:v5
+        # image: gcr.io/google-samples/gb-frontend:v4
         resources:
           requests:
             cpu: 100m
@@ -26,13 +28,5 @@ spec:
         env:
         - name: GET_HOSTS_FROM
           value: dns
-          # Using `GET_HOSTS_FROM=dns` requires your cluster to
-          # provide a dns service. As of Kubernetes 1.3, DNS is a built-in
-          # service launched automatically. However, if the cluster you are using
-          # does not have a built-in DNS service, you can instead
-          # access an environment variable to find the master
-          # service's host. To do so, comment out the 'value: dns' line above, and
-          # uncomment the line below:
-          # value: env
         ports:
         - containerPort: 80