Add migrate command for legacy HPAs

There are current broken HPAs floating around that either use the legacy
oapi DeploymentConfig defintion (`v1.DeploymentConfig`) or the incorrect
API group, due to the webconsole (all scalables, but with the group as
`extensions/v1beta1`).  This introduces a migrate command that corrects
the ScaleTargetRef of those HPAs to have correct API groups that are
usable by generic scale clients.

Author: DirectXMan12

contrib/completions/bash/oc

@@ -21,6 +21,7 @@ import (
 	migrateauthorization "github.com/openshift/origin/pkg/oc/admin/migrate/authorization"
 	migrateetcd "github.com/openshift/origin/pkg/oc/admin/migrate/etcd"
 	migrateimages "github.com/openshift/origin/pkg/oc/admin/migrate/images"
+	migratehpa "github.com/openshift/origin/pkg/oc/admin/migrate/legacyhpa"
 	migratestorage "github.com/openshift/origin/pkg/oc/admin/migrate/storage"
 	"github.com/openshift/origin/pkg/oc/admin/network"
 	"github.com/openshift/origin/pkg/oc/admin/node"
@@ -97,6 +98,7 @@ func NewCommandAdmin(name, fullName string, in io.Reader, out io.Writer, errout
 					migratestorage.NewCmdMigrateAPIStorage("storage", fullName+" "+migrate.MigrateRecommendedName+" storage", f, in, out, errout),
 					migrateauthorization.NewCmdMigrateAuthorization("authorization", fullName+" "+migrate.MigrateRecommendedName+" authorization", f, in, out, errout),
 					migrateetcd.NewCmdMigrateTTLs("etcd-ttl", fullName+" "+migrate.MigrateRecommendedName+" etcd-ttl", f, in, out, errout),
+					migratehpa.NewCmdMigrateLegacyHPA("legacy-hpa", fullName+" "+migrate.MigrateRecommendedName+" legacy-hpa", f, in, out, errout),
 				),
 				top.NewCommandTop(top.TopRecommendedName, fullName+" "+top.TopRecommendedName, f, out, errout),
 				image.NewCmdVerifyImageSignature(name, fullName+" "+image.VerifyRecommendedName, f, out, errout),