Added ANTLR. Fix Issue #20960

[DavidGrath]

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I'm taking inspiration from #3715 by @sullis and #11738 by @borsch to try and add parsing utilities for Kotlin and possibly other languages. For now, though, it's just to fix this issue.
Kotlin Grammar gotten from https://github.com/antlr/grammars-v4

@4brunu, please help review

[wing328]

thanks for the PR

please review the build failure when you've time

[wing328]

what about using spaces instead of tabs?

shall we fix the javadoc issue instead of excluding these from the tests?

[DavidGrath]

Good Day,
I'm not sure what you mean exactly, so please can you help me to clarify?
My main issue comes from the fact that it seems the JavaDoc plugin doesn't recognize the ANTLR packages because the dependency is in test scope.
Are you saying that instead of excluding the generated files from scanning, I should find a way to let them be scanned without also causing classpath issues?
Also, sorry about the inconsistent whitespace, I'll fix it

[wing328]

My main issue comes from the fact that it seems the JavaDoc plugin doesn't recognize the ANTLR packages because the dependency is in test scope.

👌

please ignore my comment on that

[DavidGrath]

Okay. Tabs removed from the pom files

[wing328]

thanks for the PR

let's give it a try

cc @OpenAPITools/generator-core-team

[DavidGrath]

Thank you