implement pages#index view
implement pages#index controller
add h1 to pages#new view
add pages#edit route
add pages#edit action
create pages#edit view
implement pages#edit view
implement pages#edit action
refactor pages#new and pages#edit views
refactor pages#new and pages#edit actions (private method)
refactor pages#new and pages#edit actions (before action)
add pages#update routes
add pages#update action
implement pages#update action