title: Custom page in ActiveAdmin
body: <p>I created a new custom page with a non-ActiveAdmin controller. The view is at
  <code>app/views/messages/new.html.erb</code> instead of <code>app/views/admin/help</code>.
  I tried to reference the template path:</p>
  
  <pre><code>ActiveAdmin.register_page "Help" do
    content do
      render :partial =&gt; 'messages/new'
    end
  end 
  </code></pre>
  
  <p>but didn't work (ActionView::MissingTemplate). </p>