opusfile: Data Structures

| opusfile 0.10 Stand-alone decoder library for .opus files.

Data Structures
Here are the data structures with brief descriptions:

C OpusFileCallbacks | The callbacks used to access non-`FILE` stream resources
C OpusHead | Ogg Opus bitstream information
C OpusPictureTag | The contents of a METADATA_BLOCK_PICTURE tag
C OpusServerInfo | HTTP/Shoutcast/Icecast server information associated with a URL
C OpusTags | The metadata from an Ogg Opus stream