Add support for CJ queries

:-)
You'll be calling `serialize_queries` twice here. Maybe make a helper function, e.g.

```ruby
    result[:queries] = serialize_queries(resource) if forms_for_queries(resource).any?

# <snip>

def forms_for_queries(resource)
  resource.forms.select { |form| form.method == 'GET' }
end
```