SoyAjaxController: provide support for namespace

[matiwinnetou]

As our frontend dev said it would be good if compiled templates supported
requirejs or even without requirejs one could wrap them inside another function to limit the namespace. This is important because it will not register compiled files as global java functions which is not very good in terms of performance and also could lead to name collisions.

Example call when feature is available:
www.domain.com/soy/hash/index?namespace=myNamespace

and the output js will be wrapped inside a var myNamespace = function() {
}

[matiwinnetou]

I need to learn more about requirejs in order to implement this

[matiwinnetou]

Speak with Uwe about this because I think library supports namespaces based on soy namespace