URI Parameters are only populated with the last URI Parameter

I've been using the raml-jaxrs-codegen project and found an issue with the PathParam generation.

Let's say my RAML file has the following URIs:
```
/posts:
  /{postId}:
    /{commentId}:
```

In the generated interface, the method corresponding to the {commendId} will ONLY contain a single PathParam, but I expect 2 PathParams (one for postId, one for commentId).

This issue stems from a class in the raml-java-parser project -- to be specific, the class "org.raml.parser.visitor.RamlDocumentBuilder" and the function "populateDefaultUriParameters"
In this function, URI Parameters are only created for the last URI parameter, instead of all the URI parameters.