Update 3rd party JavaScript libraries and plugins.

* Update to jQuery v1.11.1 (from jQuery's own CDN for now as Google APIs hasn't got it yet).
* Update to ColorBox v1.5.9.
* Update to Masonry v3.1.5.
* Update to Web Font Loader v1.5.3.
* Update to imagesLoaded v3.1.5 (v3.1.6 is out but not available via Bower yet).
* Update to Modernizr 2.8.1.
* Switch from using masonry.pkgd and imagesLoaded.pkgd to build them via Grunt – this saves a few bytes since we only include eventie and EventEmitter (used by both) once.