* Authentication and database selection should be handled transparently by 
  the client.

* The current behaviour of sending, by default, unshardable commands to the 
  first registered connection of a ConnectionCluster instance needs to be 
  verified.

* The included test suite covers almost all the Redis server commands, but a 
  full battery of tests targeting specific functions of this library is still 
  missing.

* Support for pipelining commands on one or more connections works, but it 
  could be optimized for better performances with a cache of computed commands 
  hashes, but the memory impact still needs to be evalued.

* Add the possibility of flushing the command buffer from inside of a pipeline.

* Switching to/from instances of Connection and ConnectionCluster should be 
  transparent to the user. Using a ConnectionCluster instance when there is 
  only one active connection has an unnecessary overhead.