title: Add a class to each select options with SimpleForm
body: <p>I want to build a <code>select</code> input from an array (and not a collection of models), with SimpleForm, and have different classes for each <code>option</code>s.</p>
  
  <p>I would have hoped that this would work:</p>
  
  <pre><code>f.input :method, collection: [
      ["option text", "option_value_1", { class: "class_name_1" }],
      ["option text 2", "option_value_2", { class: "class_name_2" }]
  ]
  </code></pre>
  
  <p>The problem with that is it will generate:</p>
  
  <pre><code>&lt;select&gt;
      &lt;option value="option text" class="class_name_1"&gt;option text&lt;/option&gt;
      &lt;option value="option text 2" class="class_name_2"&gt;option text 2&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>How can I do what I want (value should be "option value") with simple form?</p>