kubeadm-config: include new commands (#8862)

Add notes and includes for these new commands in 1.11:
- kubeadm config print-default
- kubeadm config migrate
- kubeadm config images list
- kubeadm config images pull

Include placeholder generated files for the above.

Author: neolit123

content/en/docs/reference/setup-tools/kubeadm/generated/kubeadm_config_images_list.md

@@ -0,0 +1,5 @@
+PLACEHOLDER FILE UNTIL WE GENERATE THE REAL THING. DO NOT REMOVE FROM 1.11 DOCS BRANCH
+
+### Synopsis
+
+Print a list of images kubeadm will use.

content/en/docs/reference/setup-tools/kubeadm/generated/kubeadm_config_images_pull.md

@@ -0,0 +1,5 @@
+PLACEHOLDER FILE UNTIL WE GENERATE THE REAL THING. DO NOT REMOVE FROM 1.11 DOCS BRANCH
+
+### Synopsis
+
+Pull images used by kubeadm.

content/en/docs/reference/setup-tools/kubeadm/generated/kubeadm_config_migrate.md

@@ -0,0 +1,5 @@
+PLACEHOLDER FILE UNTIL WE GENERATE THE REAL THING. DO NOT REMOVE FROM 1.11 DOCS BRANCH
+
+### Synopsis
+
+migrate config from one version to another.

content/en/docs/reference/setup-tools/kubeadm/generated/kubeadm_config_print-default.md

@@ -0,0 +1,5 @@
+PLACEHOLDER FILE UNTIL WE GENERATE THE REAL THING. DO NOT REMOVE FROM 1.11 DOCS BRANCH
+
+### Synopsis
+
+print default config.

content/en/docs/reference/setup-tools/kubeadm/kubeadm-config.md

@@ -16,6 +16,11 @@ You can execute `kubeadm config view` to view the ConfigMap. If you initialized
 kubeadm v1.7.x or lower, you must use `kubeadm config upload` to create the ConfigMap before you
 may use `kubeadm upgrade`.
 
+In Kubernetes v1.11.0, some new commands were added. You can use `kubeadm config print-default`
+to print the default configuration and `kubeadm config migrate` to convert your old configuration
+files to a newer version. `kubeadm config images list` and `kubeadm config images pull` can be used
+to list and pull the images that kubeadm requires.
+
 {{% /capture %}}
 
 {{% capture body %}}
@@ -27,6 +32,19 @@ may use `kubeadm upgrade`.
 
 ## kubeadm config view {#cmd-config-view}
 {{< include "generated/kubeadm_config_view.md" >}}
+
+## kubeadm config print-default {#cmd-config-print-default}
+{{< include "generated/kubeadm_config_print-default.md" >}}
+
+## kubeadm config migrate {#cmd-config-migrate}
+{{< include "generated/kubeadm_config_migrate.md" >}}
+
+## kubeadm config images list {#cmd-config-images-list}
+{{< include "generated/kubeadm_config_images_list.md" >}}
+
+## kubeadm config images pull {#cmd-config-images-pull}
+{{< include "generated/kubeadm_config_images_pull.md" >}}
+
 {{% /capture %}}
 
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