Encode from unicode before writing to stdout, stderr.

[ronindesign]

Fixes encoding issue in non-specific sys.stdout.encoding=None environment. See #201

[yannmh]

Thanks a lot for writing the fix @ronindesign 🙇

[ronindesign]

You're welcome. I'm working on a more complete patch for unicode support in dogshell.wrap that is downstream from this, but I wanted to fast track this fix so the printing would at least work.