When using the form_for helper in the example, we need to use users_path and not…

When using the form_for helper in the example, we need to use users_path and not user_path (which will point to the show action instead of the create action).

README.md

@@ -109,7 +109,7 @@ In your migrations:
 
 In your edit and new views:
 
-    <%= form_for @user, :url => user_path, :html => { :multipart => true } do |form| %>
+    <%= form_for @user, :url => users_path, :html => { :multipart => true } do |form| %>
       <%= form.file_field :avatar %>
     <% end %>