Add bootstrap confidence intervals from Neil Toronto
Use bootstrapping for confidence intervals and delete dead code

- Currently getting a division by 0 in bootstrap-bca-conf
- Should break up this commit once problems solved
Fixed bootstrap-bca-conf.

Thanks to Neil Toronto for the fix.
Fix bootstrapping integration.
Switch to LGPL.

For consistency with other Racket libraries.
Add more info to logging.
Document progress logging.
Remove warning. Problem has been solved.
Fix result loading to not require files 1..n to all exist.