Allow use of a numeric value in data-slide to create carousel controls that navigate directly to the slide with the given index

Created by: mwhitneysdsu

Added a unit test to previously closed submission.

Example:

<a class='thumbnail carousel-control' href='#myCarousel' data-slide='1'><img src='assets/images/main/NAIOP2011-150w.jpg' alt='Click this image to navigate the carousel to the second image' /></a>