Add an option to configure the failure level and fail the task accordingly

[ggrossetie]

Asciidoctor can return a non-zero exit code if specified logging level is reached. For instance, it can be useful when you want to fail if an include directive is not found (by setting failure_level to WARN).

In the context of Gradle, I think we should probably throw an exception to fail the task.

I can submit a pull request with a few guidance on how to (properly) fail task.

[ysb33r]

Closed. Will be in 3.2.0

[abelsromero]

Trying to test this I see this only works in tasks with

asciidoctor {
    failureLevel 'ERROR'
}

But failureLevel is not valid in the extension

asciidoctorj {
}

Is that intended?

[ysb33r]

asciidoctor {
  asciidoctorj {
    failureLevel 'ERROR'
 }
}