add review feature

create a review model which has belongs_to relationship with profile.
add attributes user_id, profile_id, comment and rating to review
create a review controller which creates and destroys a review

I think review should be nested inside profile like:
 resources :profiles, only: [:new, :create] do
      resources :reviews, only: [:new, :create, :show]
end

This will work well with --@review = @profile.reviews in the profile_controller.rb