public IEnumerable <Movie> SelectTopFiveMovies()
{
var averageRatings = _movieRatingRepository.GetRatings()
.GroupBy(m => m.MovieId)
.Select(g => new MovieRating {
MovieId = g.Key, Rating = g.Average(r => r.Rating)
});
return(SortTopMovies(averageRatings).Take(5));
}