Add indexing to skeleton track encoding as per the spec at http://github.com/cpearce/OggIndex/blob/skeleton-index-per-stream/
patch (patch by Chris Pearce)

Wrap writing encoded ogg pages to disk in a function which determines whether the output file is seekable the first time you write a page.
(patch by Chris Pearce)

changes the SConstruct file so that library dependencies are determined independently. This means that if you're missing one of the ogg libraries, it tells you specifically which one you're missing, rather than saying vaguely you're missing one of four possible libraries. (patch by Chris Pearce)

* use TH_ENCCTL_SET_DUP_COUNT for frames that are inserted to maintain sync
* add --nosync to get old behavior, --sync is now default
thanks to Jason and Anton for hunting this down and providing a patch

metadata specified with --artist etc overrides it.
also added --nometadata to not read metadata from input file
patch by Anton Novikov