* rework reference counting in the client libraries: now refcounting goes

* rework reference counting in the client libraries: now refcounting goes
  strictly "one-way" - the "bigger" object refcounts the "smaller" one, never the
  other way round.

* when registering for a reply packet in pdispatch, specify a function that is
  called when the pdispatch object is destroyed but the reply hasn't yet been
  recieved.

* move prototype of pa_free_cb from stream.h to def.h

git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@794 fefdeb5f-60dc-0310-8127-8f9354f1896f