Improved handling of audio retrieval.
Added transcode option to configuration.
Added author annotation to class.
Added documentation and format configuration.
Updated TranscodeAudio significantly.

- Translated tabs to spaces.
- Extracted some functionality into separate method.
- Moved certain configuration values into external configuration
  file.
- Overall, optimized for testability.
Translate tabs to space.
Added author annotation.
Make use of configuration directives for transcoding.
Extract Media instantiation into separate function.
Modified transcoding behaviour to ease testing.
Added some tertiary test coverage for TranscodeAudio.