title: Is there an easier way of creating/choosing related data with ActiveAdmin?
body: <p>Imagine I have the following models:</p>
  
  <pre><code>class Translation &lt; ActiveRecord::Base
    has_many :localizations
  end
  
  class Localization &lt; ActiveRecord::Base
    belongs_to :translation
  end
  </code></pre>
  
  <p>If I do this in ActiveAdmin:</p>
  
  <pre><code>ActiveAdmin.register Localization do
    form do |f|
      f.input :word
      f.input :content
    end 
  end
  </code></pre>
  
  <p>The association for word will only allow me to choose from existing words. However, I'd like to have the option of creating a new word on the fly. I thought it may be useful to accept nested attributes in the localization model ( but then, I will only have the option of creating a Word, not selecting from existing ones ). How can I solve this problem?</p>