Add a task to update the javascripts, stylesheets, and images.
user
```ruby
namespace :datepicker do
   require 'fileutils'
   
   desc "Replace the old javascript and CSS files with the new ones"
   task :update do
      js_dir = File.dirname(__FILE__) + '/../../../../public/javascripts/'
      datepicker_js = js_dir + 'datepicker.js'
      lang_dir = js_dir + 'lang'
      datepicker_css = File.dirname(__FILE__) + '/../../../../public/stylesheets/datepicker.css'
      images_dir = File.dirname(__FILE__) + '/../../../../public/images/datepicker'

      FileUtils.cp File.dirname(__FILE__) + '/../public/javascripts/datepicker.js', datepicker_js
      FileUtils.cp_r File.dirname(__FILE__) + '/../public/javascripts/lang/', lang_dir
      FileUtils.cp File.dirname(__FILE__) + '/../public/stylesheets/datepicker.css', datepicker_css
      FileUtils.cp_r File.dirname(__FILE__) + '/../public/images/', images_dir
   end
end
```
assistant