Remove jQuery & json2 from new app generator

[zohararad]

Seems like these are dependencies that should be handled outside the scope of a Spine application, in particular now that Spine supports Zepto as well

[whatyoubendoing]

@zohararad Ive added more documentation, surrounding the actual gem dependencies, I've also added us as contributors to the read me. Maybe we need to work out which gems are installed and generate the sprockets dependencies based on that?

[zohararad]

Hmm... I think that the bare minimum JS dependencies should be added.

Any dependencies that you find irreplaceable or required for a new Spine app?