This makes "sprockets/railtie" explicit. This means that sprockets will be loaded when you require "rails/all". If you are not using requiring "rails/all", you need to manually load it with all other framework railties. In order to be complete, this commit also adds --skip-sprockets to the rails generator.
This group is required by default only on development and test (you can change it on config/application.rb). `rake assets:precompile` will automatically add the assets group to Rails.groups (and consequently Bundler.require) and should work transparently.