Things that need to be done
- decode user provided log messages from locale encoded byte strings to unicode strings
- decode logfile if --logfile option used
- decode the message specified in command line if --message option used
- decode edited file otherwise
- use terminal encoding to display those messages (provided as unicode strings)
- encode log messages (provided as unicode string) in UTF-8 when storing
- decode log messages from UTF-8 to unicode string when retrieving