add 'images' documentation

deprecate 'imageTags' documentation

examples/image.md

@@ -0,0 +1,76 @@
+# Demo: change image names and tags
+
+
+Define a place to work:
+
+<!-- @makeWorkplace @test -->
+```
+DEMO_HOME=$(mktemp -d)
+```
+
+Make a `kustomization` containing a pod resource
+
+<!-- @createKustomization @test -->
+```
+cat <<EOF >$DEMO_HOME/kustomization.yaml
+resources:
+- pod.yaml
+EOF
+```
+
+Declare the pod resource
+
+<!-- @createDeployment @test -->
+```
+cat <<EOF >$DEMO_HOME/pod.yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: myapp-pod
+  labels:
+    app: myapp
+spec:
+  containers:
+  - name: myapp-container
+    image: busybox:1.29.0
+    command: ['sh', '-c', 'echo The app is running! && sleep 3600']
+  initContainers:
+  - name: init-mydb
+    image: busybox:1.29.0
+    command: ['sh', '-c', 'until nslookup mydb; do echo waiting for mydb; sleep 2; done;']
+EOF
+```
+
+The `myapp-pod` resource declares an initContainer and a container, both use the image `busybox:1.29.0`.
+The image `busybox` and tag `1.29.0` can be changed by adding `images` in `kustomization.yaml`.
+
+
+Add `images`:
+<!-- @addImages @test -->
+```
+cd $DEMO_HOME
+kustomize edit set image busybox=alpine:3.6
+```
+
+The folowing `images` will be added to `kustomization.yaml`:
+> ```
+> images:
+> - name: busybox
+>   newName: alpine
+>   newTag: 3.6
+> ```
+
+Now build this `kustomization`
+<!-- @kustomizeBuild @test -->
+```
+kustomize build $DEMO_HOME
+```
+
+Confirm that this replaces _both_ busybox images and tags for `alpine:3.6`:
+
+<!-- @confirmImages @test -->
+```
+test 2 = \
+  $(kustomize build $DEMO_HOME | grep alpine:3.6 | wc -l); \
+  echo $?
+```