fix: register custom alias provided by the user if present

[kpodsiad]

fixes #8, although I'm not sure what exactly semantic of auto alias should be and if my fix is not breaking other things. Unit tests are passing but maybe it'll be worth to have scripted test to see if aliases are working?

[reibitto]

Oops, yeah, that's definitely a mistake on my part when refactoring. Your fix here looks good to me. I'm not sure why I didn't have warnings as failures in this project. I'll have to fix that next.

I'm actually not sure how to write an integration test for sbt plugins and check its internal state, but I could at the very least add a test to make sure the sbt command in the data structure is correct. The only tests that currently exist test the rendering.

Thanks for the PR!

[kpodsiad]

I'm actually not sure how to write an integration test for sbt plugins and check its internal state, but I could at the very least add a test to make sure the sbt command in the data structure is correct. The only tests that currently exist test the rendering.

I have some experience with scripted tests, I can take a look and try to write one. I think internal state doesn't need to be inspected, all what we need to check is if an alias invokes a command and doesn't result in error instead.