Complete reorganization of the Predis\Connection namespace.

* Renamed SingleConnectionInterface to NodeConnectionInterface since
  this name is better and makes even more sense in the context of
  cluster and replication scenarios.

* Moved specialized aggregate connections (the ones implementing both
  predis and redis cluster and master/slave replication) in a newly
  created Predis\Connection\Aggregate sub-namespace.

* Removed the "Connection" part from names of aggregate connection
  interfaces in the Predis\Connection\Aggregate sub-namespace.

* Changed "Composable" to "Composite" in the name of interfaces and
  classes that can use pluggable protocol processors.

lib/Predis/Connection/AbstractConnection.php

@@ -22,7 +22,7 @@ use Predis\Protocol\ProtocolException;
  *
  * @author Daniele Alessandri <suppakilla@gmail.com>
  */
-abstract class AbstractConnection implements SingleConnectionInterface
+abstract class AbstractConnection implements NodeConnectionInterface
 {
     private $resource;
     private $cachedId;