Log printed labels to stdout

[pklaus]

See ba35a10 and 5d079b8
Those are commits from @Jeroen684 from PR #16. They also silence bottle's web server log on stdout.

I put this here for me as a reminder while merge-closing the PR otherwise (merging only the commit about the file encoding the PR was about originally).

[pklaus]

The biggest issue I see is the fact that the code is logging to a hard-coded file printhistory.log. It should be configurable. (And possibly default to stdout?)