Grunt 0.4, add imagesloaded dependancy and bump required jQuery to 1.5

Grunt 0.4 is now used for the build system, with many changes to the core
Gruntfile and required contrib modules.

Removed custom imagesLoaded method and added imagesLoaded library
dependancy instead. Deferreds are now handled much better and can be
used for both content.text and content.title options.

Updated package.json and qTip2.jquery.json file