Merge pull request #1376 from gmarik/patch-1

removes duplication

lib/paperclip/content_type_detector.rb

@@ -46,15 +46,13 @@ module Paperclip
     def empty_file?
       File.exists?(@filename) && File.size(@filename) == 0
     end
+    
+    alias :empty? :empty_file?
 
     def blank_name?
       @filename.nil? || @filename.empty?
     end
 
-    def empty?
-      File.exists?(@filename) && File.size(@filename) == 0
-    end
-
     def possible_types
       MIME::Types.type_for(@filename).collect(&:content_type)
     end