Log-Style Output

[geoffreywiseman]

For batch mode, it might be preferable to offer a log style of output:

Prune execution begins.
Removing file 'mysql-backup-2012-01-01.sql' (Older than two weeks).
Prune execution complete.

Not sure how much work this kind of output shift would be -- so deferring it for now, until I get a better sense of how the output looks in logs with quieter output.