PyJobTransforms: More py3 unicode fixes

Athena emits some log messages that contain unicode characters. With python 3, this will causes crashes in trfExe if the logging sinks aren't set up with the proper encoding. Depending on the setting of LANG, they may not be.

Explicitly open logging files with utf-8 encoding. If sys.stdout is using an ascii/ansi encoding, then open a new stream with the same fileno with utf-8 encoding.