Refactor validation and operation logging

[ydahhrk]

The code currently hardcodes the type (validation vs operation) of each log. It's a lousy solution, because some code runs in both contexts, which might result in logging being dumped in the wrong output.

Instead, the logging subsystem should probably decide log type based on whether it's being called from a validation thread or not.

Also, I'm fantasizing about moving validation messages into a prettier, optional report. Likely Fort 2.0 material.