Bug #12, Extending AccessifyHTML5 to add WAI-ARIA roles to HTML 4*

* That is, roles for arbitrary legacy HTML containing <div> etc,
* AccessifyHTML5(): argument 1 unchanged, argument 2 added,
* Commit adds support for `aria-label` attributes etc,
* Todo: add support for `aria-labelledby`,
* #13, `bjs1` unit test still passes + new `bjs2` - BusterJS.