Add upstream plugins

Signed-off-by: Adrian Nöthlich <git@promasu.tech>

wp-content/plugins/all-in-one-event-calendar/lib/cache/interface.php

@@ -0,0 +1,52 @@
+<?php
+
+/**
+ * Interface for cache engines.
+ *
+ * @author     Time.ly Network, Inc.
+ * @since      2.0
+ * @package    Ai1EC
+ * @subpackage Ai1EC.Cache
+ */
+interface Ai1ec_Cache_Interface {
+
+    /**
+     * Set entry to cache.
+     *
+     * @param string $key   Key for which value must be stored.
+     * @param mixed  $value Actual value to store.
+     *
+     * @return bool Success.
+     */
+    public function set( $key, $value );
+
+    /**
+     * Add entry to cache if one does not exist.
+     *
+     * @param string $key   Key for which value must be stored.
+     * @param mixed  $value Actual value to store.
+     *
+     * @return bool Success.
+     */
+    public function add( $key, $value );
+
+    /**
+     * Retrieve value from cache.
+     *
+     * @param string $key     Key for which to retrieve value.
+     * @param mixed  $default Value to return if none found.
+     *
+     * @return mixed Previously stored or $default value.
+     */
+    public function get( $key, $default = NULL );
+
+    /**
+     * Delete value from cache.
+     *
+     * @param string $key Key for value to remove.
+     *
+     * @return bool Success.
+     */
+    public function delete( $key );
+
+}