Bugfix: fix problems introduced by sloppy security fix There commit "Security: Prevent editing/deleting menu items from different menus" had a number of mistakes: - Used $item (an object), when it should have used $item_id (a number) to represent the item id. - The edit functions are also called by the add function, so if item id is not defined, it is not a bug. - The 'fast' mode was used to load the menus, but fast mode does not load menu items. - This caused the menu item validator to not work because there were no menu items loaded into the menu! Other related fixes/improvements were made: - Pass the access_type_id to the form so that the validate functions can use it instead of menu_id.