Help message for Argument could be improved

[benasher44]

In realm/SwiftLint#1191, I'm adding an Argument. For an Argument initialized like this:

Argument(defaultValue: [""], usage: "list of paths to the files or directories to \(action)")

I get a help message that looks like this:

[[""]]
	list of paths to the files or directories to lint

It'd be nice if instead it looked more like this (to match arg interfaces in other cli tools):

[<paths…>]
	list of paths to the files or directories to lint

This may require the inclusion of a 3rd parameter to Argument called variableName.

[mdiep]

Want to open a PR for this? 🙂

[benasher44]

Done! I didn't think I'd have time to do this initially :)