Allow unicode filenames on WaveFile and RecordingWaveFile

Ignore-this: e0f9d241d7e5dcb3f80e99e9ae80c75b

darcs-hash:20120910123356-56b4d-4d3485286a37b619b36651aeda4ac5e7870eeea8
Raised core revision

Ignore-this: 381ed10a6f9ccea8c9aa4c005c805c77

darcs-hash:20120910124924-56b4d-2ca83df0e29959439776a3f037e0473d6fec46ac