+ Concept of PluginModule and inherited classes such as ServerModule, MenuModule, ...

* Client now tracks current menu module. Auto detach events, etc.

core/plugin_module.js

@@ -0,0 +1,7 @@
+/* jslint node: true */
+'use strict';
+
+exports.PluginModule	= PluginModule;
+
+function PluginModule() {
+}