Could this be implemented as part of the existing `link` DSL method? Other formats such as HAL also support link templates and it looks like this could be part of the generic link DSL. For example

```
link 'user.managers', href: "http://foo.bar.com/{user.id}/managers", templated: true
```

I don't particularly like overloading methods with hash options too much, but it looks like many adapters could benefit from link templates.