title: Paperclip how to change basename (filename)?
body: <p>I am trying to change the basename (filename) of photos:</p>
  
  <p>In my model I have:</p>
  
  <pre><code>  attr_accessor :image_url, :basename
  
    has_attached_file :image,
            :styles =&gt; { :original =&gt; ["300x250&gt;", :png], :small =&gt; ["165x138&gt;", :png] },
            :url  =&gt; "/images/lille/:style/:id/:basename.:extension",
            :path =&gt; ":rails_root/public/images/lille/:style/:id/:basename.:extension"
  before_save :basename
  private
  
    def basename
    self.basename = "HALLLO"
    end
  </code></pre>
  
  <p>But the filename is not changed at all. </p>