Menubar: Remove buttons option. We only have one default visual style, customizations can happen via CSS
Menubar: Change menuIcons option to icons option, with a single 'menu' property, along with unit test. Move things from the default demo to the visual test and extend that to cover the new option as well as custom markup.
Menubar: Add missing 'select' callback option default.
Remove popup widget and its usage in menu
Menubar: Revert option formatting changes, fix commons unit test by including the valid select callback
Menubar: Format CSS source file, change 'dashed' to 'solid' (not visible, now less irritating)
Menubar: Move tests around, to more appropriate files
Menubar: Improve focus handling, keep it on last focused item when tabbing away and back, with unit test
Menubar: Rename menuElement option to menus, makes it consistent with Menu's menus option
Menubar: Rename icons.menu to icons.dropdown
Menubar: Fix more bugs in the brittle focus handling code. Including crappy tests. Needs to be redone.
Menubar: Add adminbar demo. Clean up default demo.
Menubar: Some code review, adding TODO comments, resolving one