title: ActiveSupport::Concern running method before/after initialize
body: <p>Does <code>ActiveSupport::Concern</code> support a way to run a method before or after the object's constructed.</p>
  
  <p>e.g. to achieve something like</p>
  
  <pre><code>Module Benchmarker
  
    extend ActiveSupport::Concern
  
    before_initialize
      @constructed_at = DateTime.now
    end
  
  end
  </code></pre>
  
  <p>(Note: Not wanting this for ActiveRecord or ActiveController. Just a generic Ruby class within a Rails project.)</p>