clj-kondo support & tidy .jar

[owenRiddy]

Hi!

This addresses closed Issue #14. {:clj-kondo/config '{:lint-as {com.rpl.proxy-plus/proxy+ clojure.core/proxy}}} was suggested as a linter hint. This hint is incorrect since the syntax of proxy+ is different from proxy. To lint this properly is a little involved. Getting the directory structure right in resources/ was a pain - I think I've gotten it and I did check it.

I note that a linting hint was specifically rejected in #14 as a maintenance burden. Therefore no hard feelings if this is closed without comment. However I don't think people will figure this out for themselves without support from proxy-plus.

Also addresses #10 of test classes in the jar file.