The Ogg encoder is slightly less optimal under this configuration.  It
used to send shout data directly out of its ogg_page structures.  Now,
in the interest of encapsulation, it copies the data from its ogg_page
structures into a buffer provided by the shout audio output plugin
(see audioOutput_shout_ogg.c, line 77.)  I suspect the performance
impact is negligible.

[mk: this patch and its description was separated from Eric's patch
"Refactor and cleanup of shout Ogg and MP3 audio outputs"]