Add tabindex to all elements which do not have one yet

tabindex-for-all.js

// adding tabindex to all relevant elements which need it
// so we exclude the tabindexed elements
// tabindex = 0 will come after the positively numbered elements
// cf http://www.w3.org/TR/html401/interact/forms.html#adef-tabindex
jQuery(document).ready(function($) {
  $('a, input, select, button, textarea').not('[tabindex]').attr('tabindex',0);
});