libvorbis - non-free content?

[Martin Steghöfer]

Ralph Giles wrote:
> This section was added specifically to keep the document DFSG-free. It
> falls under the dual-license exception.

Thanks! :-)

> You can override the tag.

Done in 22fc8810.

> Should also add it to the exception list in
> https://wiki.debian.org/NonFreeIETFDocuments

Done: 
https://wiki.debian.org/NonFreeIETFDocuments?action=diff&rev1=81&rev2=82

Cheers,
Martin