Application.json - use variables. Calamari supports this, how to enable it

As i can see, this pullrequest is merged and in the current version of calamari (3.1.20):

I can see the to special variables in octopus:
Octopus.Action.Package.GenerateAppSettingsJson (the flag)
Octopus.Action.Package.AppSettingsJsonPath (the path)

The UI in octopus is not yet there, but since the logic in the allmighty Calamari, I want to use it instead of building my own application.json with the substitution syntax (
I tried this by setting the varibales in the project variables. But this dont do anything, also looks lige setting “Octopus.*” variables is ignored.
Anyway I can trigger the already implemented appsetting converter in calamari?

Hi Harald,

Thanks for getting in touch! I am sorry to say that while the functions were accidentally committed to master instead of a branch and then accidentally released, the features themselves are not supported, integrated or ready for use. I have no documentation because it isn’t complete.

I believe the matching feature will be part of 3.3 which is scheduled for the end of Jan '16