Returned API objects should have hyperlinks

[Ho-Sheng Hsiao]

POST /books

-> creates a new book, but should return something like

Location: http://api.myapi.com/books/10.json

Or

{ 'book': { ... },
'uri': 'http://api.myapi.com/books/10.json' }

Obstacles: Requires additional coupling between metaprogrammed controllers and the app itself. (Maybe store some of the this information inside the API (Engine) class).