JACK-Client 0.3.0

https://pypi.python.org/pypi/JACK-Client/0.3.0

• jack.RingBuffer, implemented by Alexandru Stan
• jack.Client.set_timebase_callback(), jack.Client.transport_query(),
  jack.Client.transport_query_struct(), with the help of Julien Acroute
• jack.Client.transport_state, jack.STOPPED, jack.ROLLING,
  jack.STARTING, jack.NETSTARTING, jack.position2dict()
• the userdata argument was removed from all callbacks
• compatibility with the official JACK installer for Windows, thanks to Julien
  Acroute