Carousel examples for APG

I have moved the two carousel examples to separate branches and the development is being tracked by issue 458 and 955:

Basic carousel example (Issue 458):
https://raw.githack.com/w3c/aria-practices/issue458-add-carousel-example/examples/carousel/carousel-1/carousel-1.html


Tabbed carousel example (Issue 955):
https://raw.githack.com/w3c/aria-practices/issue955-add-tabbed-carousel-example/examples/carousel/carousel-2/carousel-2.html


Jon