Issue #7213 - collapsed class not added correctly to non-clicked divs.

Proof of concept:
[Unmodified Bootstrap](http://brianholt.me/pages/unmodified.html)
[Bootstrap with proposed changes](http://brianholt.me/pages/modified.html)

The collapsed class is not added to the other .accordion-toggle correctly. This makes styling the .accordion-toggle for active and inactive states impossible. Corresponds with Issue #7213.

Reopened pull request with proper compiled bootstrap.min.js.