Add Movie model with model specs and schemas
Change Model "Movie" to "Dvd" for consistency

In error, the model was created with name "Movie." This is inconsistent with the Controller name. It should be noted that "DVDs" as an acronym is preferred but rails has a difficult time understanding how to split the word "DVDs." We could choose to convert the controller name to "MoviesController," however, there are DVDs that are not movies. Per the original specification, we will stick with "Dvd."