Add upstream plugins

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

wp-content/plugins/all-in-one-event-calendar/lib/cache/exception/not-set.php

@@ -0,0 +1,13 @@
+<?php
+
+/**
+ * Exception thrown when reading from cache.
+ *
+ * @author       Time.ly Network, Inc.
+ * @since        2.0
+ * @package      Ai1EC
+ * @subpackage   Ai1EC.Cache.Exception
+ */
+class Ai1ec_Cache_Not_Set_Exception extends Ai1ec_Exception {
+
+}