Add addApp function to align with bash version

[olsio]

Closes #862

[lightbend-cla-validator]

Hi @olsio,

Thank you for your contribution! We really value the time you've taken to put this together.

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[olsio]

Signed the CLA

[muuki88]

Thanks a lot for adding this feature ♥️

It would be awesome to add one sbt-test to validate that this feature works with future changes.

https://github.com/sbt/sbt-native-packager/tree/master/src/sbt-test/ash/command-line-settings

You can checkout the dev guidelines for pointers on how to run the tests.

[olsio]

Sure will have a look.

[olsio]

I added the test. It wouldn't build on MacOS so I had to find a Ubuntu machine first.

In general it might be a good idea to remove this plug-in all together and just have a single JavaAppPackaging version of the script without relying on bash. But I don't know what the implications of that would be.

[muuki88]

Awesome 👍 Thanks for the additional test.

In general it might be a good idea to remove this plug-in all together and just have a single JavaAppPackaging version of the script without relying on bash

From an engineering perspective I would agree to find the smallest common denominator and remove the additional stuff. My bare minimum bash knowledge is afraid of doing such a thing.

But I don't know what the implications of that would be.

Me neither 😂 I have merged like 1-5 pull request each year adding a bit more "bash magic" to make certain use cases work. Bash is really string escaping hell. So at this point I'm okay with maintaining an ash and bash implementation as I have to find someone willing to backport all the weird bash hacks I don't quite understand 😞

So in general yes ❤️ If you want to do it, I'll give you as much support as I can 🤗