[Feature] Reencode output files

[regorxxx]

Current Situation

Somewhat related to #65

Files are downloaded as is, except for the extract flac part. In many cases these flac files seem to be created with Lavf59.16.100 or mutagen and many of them lack MD5 checksum headers, usually found on the official flac encoder.

Suggestion / Feature Request

Some kind of ffmpeg or flac.exe command line setting to apply it to downloaded files automatically after they have been extracted.

It could be used for:

1. Conversion to multiple formats or other codecs.
2. Reencode to official flac with proper MD5 support.
3. Chose the degree of compression.
4. etc.

[exislow]

This app does not provide any re-encoding features. But you can do post processing after downloading with your favorite app.

Otherwise feel free to get me a pull request with your idea.