title: ransack with simple_form builder input_html option
body: <p>I am using ransack (1.5.1) with  simple_form (3.1.0)</p>
  
  <p>I use the following search form</p>
  
  <pre><code>&lt;%= search_form_for @search, :builder =&gt; SimpleForm::FormBuilder do |f| %&gt;
  </code></pre>
  
  <p>and the following input_field</p>
  
  <pre><code>&lt;%= f.input_field(:contact_groups_name_eq_any, input_html: { class: 'inline tight' },
                                      collection: @contact_group_names, as: :check_boxes) %&gt;
  </code></pre>
  
  <p>I get the following output:</p>
  
  <pre><code>&lt;div class="checkbox"&gt;&lt;input checked="checked" class="check_boxes required" id="q_contact_groups_name_eq_any_family" input_html="{:class=&gt;&amp;quot;inline tight&amp;quot;}" name="q[contact_groups_name_eq_any][]" value="Family" type="checkbox"&gt;&lt;label class="collection_check_boxes" for="q_contact_groups_name_eq_any_family"&gt;Family&lt;/label&gt;&lt;/div&gt;
  </code></pre>
  
  <p>Why isn't the input_html: hash updating the input class?</p>