start a restructure

Behavioral/Mediator/Subsystem/Server.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace DesignPatterns\Mediator\Subsystem;
+
+use DesignPatterns\Mediator\Colleague;
+
+/**
+ * Server serves responses
+ */
+class Server extends Colleague
+{
+    /**
+     * process on server
+     */
+    public function process()
+    {
+        $data = $this->getMediator()->queryDb();
+        $this->getMediator()->sendResponse("Hello $data");
+    }
+}