Moved cache drivers outside core to extensions (plugins)

plugins/cache-redis/Predis/Cluster/Hash/HashGeneratorInterface.php

@@ -0,0 +1,30 @@
+<?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\Hash;
+
+/**
+ * An hash generator implements the logic used to calculate the hash of a key to
+ * distribute operations among Redis nodes.
+ *
+ * @author Daniele Alessandri <suppakilla@gmail.com>
+ */
+interface HashGeneratorInterface
+{
+    /**
+     * Generates an hash from a string to be used for distribution.
+     *
+     * @param string $value String value.
+     *
+     * @return int
+     */
+    public function hash($value);
+}