Migrate all JvmTasks to use the new options system.

The common --jvm-options, --args, --debug and --confs flags now
live in the base class, but this required migrating all the
relevant tasks at once, hence the scope of this change.

This also gets rid of manual flag-to-config fallback, as the new
options system does this automatically. However this required some
changes to section and key names in pants.ini. I'm documenting
these changes in a spreadsheet, for smooth config migration in
pants install bases.

This required breaking a couple of inconsistently named flags, e.g.,
--benchmark-caliper-args is now just --benchmark-args.

Testing Done:
CI passed.

Manually tested that new flags and config settings work.

Reviewed at https://rbcommons.com/s/twitter/r/1186/