Feature/robospice retrofit

This is a result of our new and shiny robospice+retrofit+kotlin.

First, define model. (In Java, as Realm required)

```Java
public class Movie {

    private int id;
    private String title;
    private float popularityScore;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public float getPopularityScore() {
        return popularityScore;
    }

    public void setPopularityScore(float popularityScore) {
        this.popularityScore = popularityScore;
    }

    public static class ResultList {

        private List<Movie> results;

        public List<Movie> getResults() {
            return results;
        }
    }
}
```

Create API interface (in trait by using Kotlin)

``` Kotlin
trait TheMovieDBAPI {
    GET("/discover/movie")
    fun discoverMovies(Query("sort_by") sortBy: String): Movie.ResultList
}
```

Express your request with request object inherited from ```RetrofitSpiceRequest```


``` Kotlin
class DiscoverMovieSpiceRequest(val sortBy: String) :
        RetrofitSpiceRequest<Movie.ResultList, TheMovieDBAPI>(javaClass<Movie.ResultList>(), javaClass<TheMovieDBAPI>()) {

    override fun loadDataFromNetwork(): Movie.ResultList? {
        return getService().discoverMovies(sortBy)
    }

}
```

Then, make use of it like usual in controller class 

``` Kotlin
btFetchMovie.setOnClickListener { view ->
            getServiceManager().execute(DiscoverMovieSpiceRequest("popularity.desc"), EventBusResponseListener<Movie.ResultList>())
            getServiceManager().execute(DiscoverMovieSpiceRequest("vote_average.desc"), object: RequestListener<Movie.ResultList> {
                override fun onRequestFailure(spiceException: SpiceException?) {
                    toast(spiceException?.getMessage())
                }

                override fun onRequestSuccess(results: Movie.ResultList?) {
                    Log.i(tag(), results?.getResults()?.size.toString())
                }
            })

        }
```