Feature: Languages (i18n)

I think `dlv ` could support more languates, especially the `msg` for `help` (include the children of cmd) or specific error.
En, but it looks like `cobra` does not support it ([the issues for cobra](https://github.com/spf13/cobra/issues/719))

Start with the dlv help command, especially help output that includes child commands, and review the linked Cobra issue #719. Determine whether localized help and specific error messages can be supported in Delve or require Cobra changes; the issue is done only when the supported language scope and affected messages are defined.

Written by the indexing model from the issue text.