Allow kubectl get to fetch multiple resource types

Like Delete, which can now run over multiple types:

    kubectl delete pods,services -l name=foo

Get should be able to span items for label selection

    kubectl get pods,services -l name=foo

pkg/kubectl/cmd/cmd.go

@@ -28,6 +28,7 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/client/clientcmd"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/kubectl"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/kubectl/resource"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
 
@@ -42,6 +43,7 @@ const (
 
 // Factory provides abstractions that allow the Kubectl command to be extended across multiple types
 // of resources and different API sets.
+// TODO: make the functions interfaces
 type Factory struct {
 	clients *clientCache
 	flags   *pflag.FlagSet
@@ -218,6 +220,13 @@ func DefaultClientConfig(flags *pflag.FlagSet) clientcmd.ClientConfig {
 	return clientConfig
 }
 
+// ClientMapperForCommand returns a ClientMapper for the given command and factory.
+func ClientMapperForCommand(cmd *cobra.Command, f *Factory) resource.ClientMapper {
+	return resource.ClientMapperFunc(func(mapping *meta.RESTMapping) (resource.RESTClient, error) {
+		return f.RESTClient(cmd, mapping)
+	})
+}
+
 func checkErr(err error) {
 	if err != nil {
 		glog.FatalDepth(1, err)