Adds yield around resource on controllers

Adding same functionality as https://github.com/plataformatec/devise/pull/2728

Allow
class Overrided::InvitationsController < Devise::InvitationsController

  def update
    super do |resource|
      BackgroundWorker.trigger
    end
  end

end
Merge pull request #434 from bradleypriest/patch-1

Adds yield around resource on controllers