Bugs fixed:

*  authentication retry while server is loading db (danmaz74) [GH-101]
*  command arguments processing issue with arrays

New features:

*  Auto update of new commands from redis.io (Dave Hoover)
*  Performance improvements and backpressure controls.
*  Commands now return the true/false value from the underlying socket write(s).
*  Implement command_queue high water and low water for more better control of queueing.

See `examples/backpressure_drain.js` for more information.
