Developing in API mode

If you want to just make an API with Blacklight 7 (avoiding the UI components), do the following:

1. rails new my_api --api
2. Add gem 'blacklight' to the Gemfile and bundle install
3. rails generate blacklight:install
4. Add include ActionController::MimeResponds to ApplicationController in order to provide respond_to
5. Add a public/index.html to prevent blacklight from rendering the welcome message.