k8s_scale - add option label_selectors and continue_on_error (#114)

k8s_scale suppport for label selector

molecule/default/files/deployment.yaml

@@ -0,0 +1,50 @@
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: test0
+  labels:
+    app: nginx
+spec:
+  replicas: 3
+  selector:
+    matchLabels:
+      app: nginx
+  template:
+    metadata:
+      labels:
+        app: nginx
+    spec:
+      containers:
+      - name: nginx
+        image: nginx:1.14.2
+        ports:
+        - containerPort: 80
+      - name: hello
+        image: busybox
+        command: ['sh', '-c', 'echo "Hello, from test0" && sleep 3600']
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: test1
+  labels:
+    app: nginx
+spec:
+  replicas: 3
+  selector:
+    matchLabels:
+      app: nginx
+  template:
+    metadata:
+      labels:
+        app: nginx
+    spec:
+      containers:
+      - name: nginx
+        image: nginx:1.14.2
+        ports:
+        - containerPort: 80
+      - name: hello
+        image: busybox
+        command: ['sh', '-c', 'echo "Hello, from test1" && sleep 3600']