Adds scaffolding for users. #6
Adds bcrypt gem for security with users. #6
Adds sessions scaffolding. #8
Adds sessions and custom routes to routes.rb #8
Adds the model for users. #6
Adds the controller for users. #6
Adds the controller for sessions. #8
Adds to the application controller for users. #6

- current_user defines the current user
- authorize will reject and redirect if you are trying to do something
you shouldn’t.
Makes it so only authorized users can edit and update. #8
Adds a login screen. #8
Follows Rails4 convention for attr_accessible. #6

- Removes attr_accessible
- Adds user params as a private method on the controller.
Fixes the resource that should have been sessions. #8