Support alternative Links object

Links can be specified in one of two formats

```
{ self: "http://somewhere.com" }
```

or

```
{ self: 
  {
    href: "http://somewhere.com",
    meta: { 
      count: 12
    }
  }
}
```

Add the object version to the LInks implemenation

http://jsonapi.org/format/#document-links
