Fix real keyboard tab navigation between KeyboardedInput elements
Fix real keyboard tab navigation between KeyboardedInput elements

* Current react-generated KeyboardedInput "input" elements will not navigate to
  the next KeyboardedInput element upon pressing tab with a real keyboard.
* This happens because the next element in the DOM is actually a KeyboardButton
  "button". Mark these elements as non-navigable by the tab button.

xtrinch/react-touch-screen-keyboard