Call for feedback: I've implemented an AsyncHttpAppender

[mlangc]

I've spent a considerable part of my Christmas holidays putting together an AsyncHttpAppender that I want to release in
the more-log4j2 library that I'm maintaining.

My personal use-case is pushing logs to the Dynatrace Ingest API without relying on proprietary Java agents or OpenTelemetry, but the appender is generic and can be integrated with other log monitoring solutions like Datadog and Grafana.

In theory, pushing logs to these APIs is also possible with the regular HttpAppender, however its performance is not acceptable even for toy projects, since logging a few lines per second ties up an entire thread due to the synchronous nature of the HttpAppender.

Thanks to compression and batching, the AsyncHttpAppender can handle log throughputs that are multiple orders of magnitude higher than what you can achieve with the regular HttpAppender. The implementation features different strategies to deal with overload situations, and retries with exponential backoff.

I would like to release this new appender as part of more-log4j2-2.0.0 in the near future, but before doing so, I want to
collect and address any feedback you may have. You can use the snapshot release that I've pushed to Maven Central, if you want some hands-on experience without checking out the project locally.