SOLR-17697 Use picocli instead of commons-cli

[janhoy]

https://issues.apache.org/jira/browse/SOLR-17697

This PR is just a way to visualize the status of the feature branch jira/SOLR-17697-picocli.
Create PRs targeting that branch to tackle individual tasks, and then merge into this feature branch once done.

Tasks/milestones:

• Add framework
• Implement POC for a few initial tools, in parallel with commons-cli
• Solve option inheritance / MixIn
• Solve option mutual exclusivity
• Solve value-fallback to ENV
• Document in RefGuide - Auto generate?
•  All tools covered
• BATS tests green
• Proof read Usage helps
• Remove commons-cli

[xtenzQ]

Actually, I'd like to try to implement PoC for few initial tools.

upd: oh, I didnt notice there is a PR created for this

[janhoy]

upd: oh, I didnt notice there is a PR created for this

Yea, there's an in-progress exploration taking place, feel free to join the discussion about it or POC for yourself on how to solve various issues that arise. We're still trying to land on the most elegant way to introduce things, and I plan to dial down the ambitions for the other PR to do bare minimal for one or two tools, and perhaps the "start" tool. Eventually, when we start getting the grip on how things should flow, it will be easier to jump in and implement PRs for new tools, targeting this branch.