Note unicode handling.
* morituri/test/test_image_image.py:
* morituri/image/table.py:
* morituri/program/cdparanoia.py:
* morituri/common/checksum.py:
Use unicode for paths.
Use repr for path representation.
* morituri/test/test_common_checksum.py:
Add test for unicode audio file name.