[MODEL] Added missing test for Response::Records#ids
[MODEL] Added the ability to pass a custom index name to .create_index!, .delete_index! and .refresh_index!
[MODEL] Added the ability to import records into a different index/type

    Article.import index: 'my-new-index', type: 'my-other-type'
[RAILS] Added a the file with Rake tasks for importing the model(s)

Add this e.g. into the `lib/tasks/elasticsearch.rake` file in your Rails application:

    require 'elasticsearch/rails/tasks/import'

Run this command inside your application folder to display usage instructions:

    bundle exec rake -D elasticsearch
[RAILS] Added information about the provided Rake tasks into the README