Panel 0
    This example requires Firefox 3 or later to work with screen readers -- it
       uses ARIA properties without namespaces, which is now the correct
       markup.
    Use tab key to reach the tab. Once a tab has focus use:
      
        - left and right arrows to move from tab to tab. Panel is made visible when
            tab gets focus. Arrow keys do not cycle around the tabs
- ctrl-left and ctrl-right arrows behave the same as left and right arrows
- ctrl-shift-pageup / ctrl-shift-pagedown is the same as left and right arrows but WILL
            cycle around the tab order (shift was added as a modifier so as not to
            conflict with the Firefox tabbing keys)
- Ctrl-shift-tab /ctrl-tab are not implemented since these keys conflict with browser tab switching keys.