add shorthand cm for configmaps

pkg/kubectl/cmd/cmd.go

@@ -158,7 +158,7 @@ __custom_func() {
 	// and add a short forms entry in expandResourceShortcut() when appropriate.
 	valid_resources = `Valid resource types include:
    * componentstatuses (aka 'cs')
-   * configmaps
+   * configmaps (aka 'cm')
    * daemonsets (aka 'ds')
    * deployments (aka 'deploy')
    * events (aka 'ev')

pkg/kubectl/kubectl.go

@@ -34,7 +34,7 @@ const (
 	PossibleResourceTypes = `Possible resource types include (case insensitive): pods (aka 'po'), services (aka 'svc'), deployments (aka 'deploy'),
 replicasets (aka 'rs'), replicationcontrollers (aka 'rc'), nodes (aka 'no'), events (aka 'ev'), limitranges (aka 'limits'),
 persistentvolumes (aka 'pv'), persistentvolumeclaims (aka 'pvc'), resourcequotas (aka 'quota'), namespaces (aka 'ns'),
-serviceaccounts (aka 'sa'), ingresses (aka 'ing'), horizontalpodautoscalers (aka 'hpa'), daemonsets (aka 'ds'), configmaps,
+serviceaccounts (aka 'sa'), ingresses (aka 'ing'), horizontalpodautoscalers (aka 'hpa'), daemonsets (aka 'ds'), configmaps (aka 'cm'),
 componentstatuses (aka 'cs), endpoints (aka 'ep'), petsets (alpha feature, may be unstable) and secrets.`
 )
 
@@ -148,6 +148,7 @@ var shortForms = map[string]string{
 	// Please keep this alphabetized
 	// If you add an entry here, please also take a look at pkg/kubectl/cmd/cmd.go
 	// and add an entry to valid_resources when appropriate.
+	"cm":     "configmaps",
 	"cs":     "componentstatuses",
 	"deploy": "deployments",
 	"ds":     "daemonsets",