Added initial admin system natives

Added a few API changes to the admin system
Exposed more interfaces

--HG--
extra : convert_revision : svn%3A39bc706e-5318-0410-9160-8a85361fbb7c/trunk%40341

core/systems/PluginSys.cpp

@@ -1249,6 +1249,8 @@ void CPluginManager::OnSourceModAllInitialized()
 	g_PluginIdent = g_ShareSys.CreateIdentType("PLUGIN");
 
 	g_RootMenu.AddRootConsoleCommand("plugins", "Manage Plugins", this);
+
+	g_ShareSys.AddInterface(NULL, this);
 }
 
 void CPluginManager::OnSourceModShutdown()