The RIA refactoring moved velero.RestoreItemAction into a separate
(restoreitemaction) v1 package. Unfortunately, this change would require
plugins to make code changes to locate the RestoreItemActionExecuteInput
and RestoreItemActionExecuteOutput structs.
This commit restores those structs to the original velero package, leaving
just the RestoreItemAction interface in the new v1 package.
Signed-off-by: Scott Seago <sseago@redhat.com>