No way to rename value names across entire struct

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Rust Version

rustc 1.57.0 (f1edd0429 2021-11-29)

Clap Version

3.1.13

Minimal reproducible code

#[derive(Parser)]
struct Args {
    hello_world: String
}

Steps to reproduce the bug with the above code

Run the --help for the above

Actual Behaviour

Its listed as HELLO_WORLD

Expected Behaviour

A way to rename it to hello-world

Additional Context

This is split out of #3282.

Proposed solution

• Rename rename_all_env to rename_env
• Add rename_value_name
• Add rename_long
• Add rename_command
• Remove rename_all

Nothing will rename id or short.

Debug Output

No response