Misc
Misc
Fixes memory leaks in ogg/vorbis encoder
Fix parameter order in buffer destroy function (!)
Fixes IO to use new ownership semantics

The new model is:

- Sources own data
		- 'pull' guarantees the data to be valid for the duration of the callback
		- 'push' becomes non-destructive

- In a similar vein, simple filters
		- own data on pull
		- are not allowed to consume data on push

TODO add this to doc

See #172