Add overloads for MenuPool.Add and UIMenu.AddItem to take params for registering multiple items at once

[pnwparksfan]

For adding menus to menu pools, and adding menu items to menus, it would be helpful to have an overload for the Add/AddItem method which takes params UIMenu[] or params UIMenuItem[] and likewise IEnumerable<UIMenu> or IEnumerable<UIMenuItem> to allow for registering multiple menus/menu items at once.