remove "users" scaffold

migration file is needed so revert db/migrate/20131103002353_create_users.rb

execute following commands;
  rails destroy scaffold users
  git checkout -- db/migrate/20131103002353_create_users.rb
  git rm app/assets/javascripts/users.js.coffee
  git rm app/assets/stylesheets/users.css.scss
  git rm app/controllers/users_controller.rb
  git rm app/helpers/users_helper.rb
  git rm app/models/user.rb
  git rm app/views/users/_form.html.erb
  git rm app/views/users/edit.html.erb
  git rm app/views/users/index.html.erb
  git rm app/views/users/new.html.erb
  git rm app/views/users/show.html.erb
  git add config/routes.rb
  git rm spec/controllers/users_controller_spec.rb
  git rm spec/helpers/users_helper_spec.rb
  git rm spec/models/user_spec.rb
  git rm spec/requests/users_spec.rb
  git rm spec/routing/users_routing_spec.rb
  git rm spec/views/users/edit.html.erb_spec.rb
  git rm spec/views/users/index.html.erb_spec.rb
  git rm spec/views/users/new.html.erb_spec.rb
  git rm spec/views/users/show.html.erb_spec.rb
execute "rails g migration drop_users"
modify drop_users migration file
execute "rake db:migrate"
Merge branch 'drop-users'