Fix guide to use correct number of files created by controller generator

In e8546ab, the Getting Started guide
was updated to reflect the removal of CoffeeScript stubs being generated
by the controller generator. However, the comment above the table of
generated files wasn't updated, so it incorrectly remained "This creates
five files and one empty directory". This fixes it to now say "This
creates four files and one empty directory".

guides/source/getting_started.md

@@ -1652,7 +1652,7 @@ controller. Again, we'll use the same generator we used before:
 $ rails generate controller Comments
 ```
 
-This creates five files and one empty directory:
+This creates four files and one empty directory:
 
 | File/Directory                               | Purpose                                  |
 | -------------------------------------------- | ---------------------------------------- |