Port gh-pages branch to bootstrap 3

Following on https://github.com/sathomas/acc-wizard/pull/18, this PR ports the demo in the gh-pages branch to support Bootstrap 3.

In fact, getting this to work was how I fixed the code from @tienvx, which is why you see commented out code for working directly off of the LESS version via less.js. A handy development option. I then minified, and converted back to using the minified versions here to test them.

Changes, questions, comments, etc welcome.