Rename interfaces and classes in the Predis\Cluster namespace.

A few methods were renamed accordingly for consistency

lib/Predis/Cluster/StrategyInterface.php

@@ -0,0 +1,42 @@
+<?php
+
+/*
+ * This file is part of the Predis package.
+ *
+ * (c) Daniele Alessandri <suppakilla@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Predis\Cluster;
+
+use Predis\Command\CommandInterface;
+
+/**
+ * Interface for classes defining the strategy used to calculate an hash
+ * out of keys extracted from supported commands.
+ *
+ * This is mostly useful to support clustering via client-side sharding.
+ *
+ * @author Daniele Alessandri <suppakilla@gmail.com>
+ */
+interface StrategyInterface
+{
+    /**
+     * Returns the hash for the given command using the specified algorithm, or null
+     * if the command cannot be hashed.
+     *
+     * @param CommandInterface $command Command to be hashed.
+     * @return int
+     */
+    public function getHash(CommandInterface $command);
+
+    /**
+     * Returns the hash for the given key using the specified algorithm.
+     *
+     * @param string $key Key to be hashed.
+     * @return string
+     */
+    public function getKeyHash($key);
+}