Reflect custom processor changes on README.md.

(thoughtbot/paperclip#1535)

README.md

@@ -501,9 +501,10 @@ a set of styles for an attachment, by default it is expected that those
 "styles" are actually "thumbnails". However, you can do much more than just
 "styles" are actually "thumbnails". However, you can do much more than just
 thumbnail images. By defining a subclass of Paperclip::Processor, you can
 thumbnail images. By defining a subclass of Paperclip::Processor, you can
 perform any processing you want on the files that are attached. Any file in
 perform any processing you want on the files that are attached. Any file in
-your Rails app's lib/paperclip\_processors directory is automatically loaded by
-paperclip, allowing you to easily define custom processors. You can specify a
-processor with the :processors option to `has_attached_file`:
+your Rails app's `lib/paperclip` and `lib/paperclip_processors` directories is
+automatically loaded by paperclip, allowing you to easily define custom
+processors. You can specify a processor with the :processors option to
+`has_attached_file`:
 
 
 ```ruby
 ```ruby
 has_attached_file :scan, :styles => { :text => { :quality => :better } },
 has_attached_file :scan, :styles => { :text => { :quality => :better } },