links for dragonfly gem in rails

 http://blog.tallgreentree.com/posts/getting-started-with-dragonfly  
 http://markevans.github.io/dragonfly/rails/  
 http://new-bamboo.co.uk/blog/2010/01/13/dragonfly  
 http://stackoverflow.com/questions/7634869/multiple-image-upload-with-dragonfly  
 error reference:  
 http://stackoverflow.com/questions/11355846/refinerycms-image-not-loading-dragonfly-error