deleted user_disability scaffold to create to scaffold - following naming conventions
added impairment scaffold to facilitate the association of disabilities with a particular user.
recreated impairment scaffold because disability_id and user_id did not need _ID at the end, since they are input by default. so previous version had user_id_id.
added radio buttons for severity when creating new impairment, add select drop displaying collection of disablities. added code in users controller to get all impairments associated with a user.
added associations.
listed impairment records on the user profile page with an option to add new impairment.
correct redirects for back link on new impairment page and after new impairment has been added.