App should support sandbox hosts

#111 broke support for sandboxes. This fixes that and also adds support for the standard wiki/ Route. @aquilax  @hakubo 
Yes,  we'll support both for now. While we are running the test, we want to emit and respond the the legacy `/wiki/` route although it's clearly arbitrary from a RESTful convention perspective. I'll have to implement support of this route in the Ember app as well. But that will largely be temporary. When Mercury is set for full production replacement of WikiaMobile, I'd like use to be using fully RESTful and semantic routes (it's better for SEO too!)