Add '-?' as an additional alias for '-h' and '--help', just like 'dotnet -?'

[kzu]

It's second nature for me to just type -? to get help on stuff. Even in the GitHub CLI, typing gh -? (although not an official option to get help) gets you the default help :).

I'd say it's a common enough shorthand for help that it deserves being supported built-in.

[patriksvensson]

Sounds like a reasonable thing to add 👍

[kzu]

Adding it as another alias/name for the Help command fails with Encountered invalid character '?' in option name.

So there are two implementation choices:

1. Make ? a valid option name in the parser
2. Convert on the fly from -? to -h before executing the app

Option 1 would make the alias discoverable, but may have unintended side-effects due to adding a character that's currently not valid.

Option 2 is easier to implement, but makes it a hidden feature.

Thoughts @patriksvensson?

For now, the PR has option 2, for simplicity reasons :)

[patriksvensson]

@kzu I have no problem making -? a valid option name. I don't think it will have any unforeseen side effects.

[kzu]

Fixed!