title: Rails 4.1 enums and simple form: how to translate them?
body: <p>While normale <code>collection</code> inputs can be easily translated</p>
  
  <pre><code>f.input :sex, collection: [:male, :female]
  </code></pre>
  
  <p>using this structure</p>
  
  <pre><code>simple_form:
    options:
      profile:
        sex:
          male: Männlich
          female: Weiblich
  </code></pre>
  
  <p>it doesn't seem to be possible to translate the new Rails 4.1 enum features.</p>
  
  <p>I tried to translate</p>
  
  <pre><code>f.input :sex, collection: f.object.class.sexes
  </code></pre>
  
  <p>like this:</p>
  
  <pre><code>simple_form:
    options:
      profile:
        sex:
          '0': Männlich
          '1': Weiblich
  </code></pre>
  
  <p>But this doesn't work. Is this a missing feature of simple form?</p>