[compiz] screenshot plugin compile fails on freebsd

[Denis F. Latypoff]

Hello list,

there is no `versionsort' implementation in the dirent.h on standard
installation of freebsd 6.x.
I have replaced `versionsort' with `alphasort' in screenshot.c, but I
don't know whether that fix will cause crash screenshot plugin since I have
not yet ran the latest git xgl/compiz/mesa on my freebsd.

-- 
Best regards,
 Denis                          mailto:latypoff at yandex.ru