Test battery upgrade: output, validate, parallelize, iterate.

1) Cleaner output.
2) Validate suites before running them, and remove tests/remote/ssh/
   (ssh messaging config is now determined by site/user config).
3) Optionally iterate the whole battery up to N times, stopping at first
   test failure (use to find intermittent problems).
4) Optionally run all suites under TOPDIR in parallel.