Optimized JLink build

[TarCV]

There are three ways to build debotc:

• usual JAR - Pro: fastest execution time, JAR is just 5MB; Con: requires Java Runtime, JAR+JRE size is huge (probably close to 400MB)
• jlinked distribution - Pro: standalone distribution, as fast as JAR build; Con: might be big (up to 50MB)
• Kotlin native build - Pro: standalone distrubtion of just one file, small (3MB); Con: slow execution

1 and 3 are mostly implemented.
2 is done on jlink branch, but probably is not optimal - it makes sense to try removing unused Kotlin modules.