implements Part 1: add movies to DB in Background steps
fixes Part 1 (movies were not added to DB); implements filter_movie_list.feature scenario 'restrict to R, PG'
implements scenario 'all ratings selected'
implements scenario 'no ratings selected'; removes debug output
implements scenarios 'sort movies alphabetically' and 'sort movies by release date'
fixes scenarios 'sort...': step definition did not really check sort order