-h, -H, and --help are all hardcoded to built-in help

[denizdogan]

It seems that it is impossible to use -h, -H or --help as they are hardcoded to throw HelpError in the parse step.

Would you be open for a PR? I would like it if this were possible:

// default: no help flags
new Command()
  .optional(c.string, ...whatever)

// -?/--help
new Command()
  .help("?", "help")
  .optional(c.string, "host", {
    flags: ["h", "host"],
    description: "omg so nice to be able to use -h again",
  })

// -h/--help
// help flag wins all conflicts
new Command()
  .help("h", "help")
  .optional(c.string, "host", {
    flags: ["h", "host"],
    description: "this will not be usable, help takes precedence",
  })

And also, I definitely think flags should be case-sensitive, so that e.g. -X is not silently transformed into -x – huge surprise when I noticed that. What do you think?