Add a couple of Kubernetes questions and exercises

In addition, changed the order of some Linux questions.

exercises/kubernetes/solutions/replicaset_02_solution.md

@@ -0,0 +1,62 @@
+## ReplicaSet 02 - Solution
+
+1. Create a ReplicaSet with 2 replicas. The app can be anything.
+
+```
+cat >> rs.yaml <<EOL
+apiVersion: apps/v1
+kind: ReplicaSet
+metadata:
+  name: web
+  labels:
+    app: somewebapp
+    type: web
+spec:
+  replicas: 2
+  selector:
+    matchLabels:
+      type: web
+  template:
+    metadata:
+      labels:
+        type: web
+    spec:
+      containers:
+      - name: httpd
+        image: registry.redhat.io/rhscl/httpd-24-rhel7
+EOL
+
+kubectl apply -f rs.yaml
+```
+
+2. Verify a ReplicaSet was created and there are 2 replicas
+
+```
+kubectl get rs
+# OR a more specific way: kubectl get -f rs.yaml
+```
+
+3. Remove the ReplicaSet but NOT the pods it created
+
+```
+kubectl delete -f rs.yaml --cascade=false
+```
+
+4. Verify you've deleted the ReplicaSet but the Pods are still running
+
+```
+kubectl get rs # no replicas
+kubectl get po # Pods still running
+```
+
+5. Create again the same ReplicaSet, without changing anything
+
+```
+kubectl apply -f rs.yaml
+```
+
+6. Verify that the ReplicaSet used the existing Pods and didn't create new Pods
+
+```
+kubectl describe rs web  # You should see there are no new events and if you list the pods with 'kubectl get po -f rs.yaml` you'll see they have the same names
+```