Upgrade jQuery to 1.11.1

* Upgrade from 1.10.2 to 1.11.1
* jQuery changes:
http://blog.jquery.com/2014/01/24/jquery-1-11-and-2-1-released/
http://blog.jquery.com/2014/05/01/jquery-1-11-1-and-2-1-1-released/
Upgrade to Bootstrap 3.2

* Upgrade from Bootstrap 3.1
* https://github.com/twbs/bootstrap/releases/tag/v3.2.0
* https://github.com/twbs/bootstrap-sass/blob/master/CHANGELOG.md
* http://blog.getbootstrap.com/2014/06/26/bootstrap-3-2-0-released/
Revert Bootstrap 3.2 change to gray-light

* This made the text on inverted navbars too dark to read, and muted
text too similar to body text.
Update docs referring to bootstrap version
Merge pull request #34 from alphagov/upgrade-libs

Update jQuery and Bootstrap