Option to persist logs?

[cmars]

Currently logs aren't persisted to files, just written on stdout. Should they be? I have mixed feelings on this one.

On one hand, piping to tee feels like the unix-y way to persist logs.

On the other hand:

• Windows may not have a tee equivalent (no idea what PS would support here)
• When distrans ships a UI front-end, a log file becomes more of a necessity
• Not sure how tee would actually deal with the spinners and progress bars, that might actually make a mess

From feedback raised in https://github.com/cmars/distrans/issues/40#issuecomment-2155867147