create movie viewing history model
Populate dashboard with last 3 movies viewed
Merge branch 'viewing_last_three_movies' of github.com:mattThousand/movie_viewing_app into viewing_last_3_movies
Modify dashboards_controller

- Add before filter to authenticate user

- Pull @movie_viewing_histories from model
Modify movies_controller

- Abstract creation of movie viewing history object to model
Create movie viewing history model
Modify dashboard view to display recently-viewed movies
Create migration for movie viewing history table

- add 'description' column
Create feature spec for 'user_views_last_3_movies_visited_spec.rb'
Modify admin dashboards view to display movie stats
Populate admin dashboards controller with data from movie model
Add method to movie model for calculating average movie rating
Create feature specs for 'admin views movie stats' user story
add failing test for unauth user visiting review show page
create ReviewViewingHistory table
add unit tests for ReviewViewingHistory

- create ReviewViewingHistory in reviews show action
Create review_viewing_history event with user authentication
Display review history on dashboard
Add pagination to dashboards controller and show view
Add authentication to admin/dashboard controller