Update docs for renaming.

README.md

@@ -523,16 +523,16 @@ details.
 [emacs-mac-port]: https://github.com/railwaycat/homebrew-emacsmacport
 [emacs-mac-port-server]: https://github.com/railwaycat/emacs-mac-port/blob/master/README-mac#L210-L213
 [homebrew]: https://github.com/Homebrew/homebrew
-[Elixir]: contrib/lang/erlang-elixir
-[Haskell]: contrib/lang/haskell
+[Elixir]: contrib/!lang/erlang-elixir
+[Haskell]: contrib/!lang/haskell
 [LaTeX]: contrib/auctex
-[JavaScript]: contrib/lang/javascript
-[Python]: contrib/lang/python
-[R]: contrib/lang/ess
-[Ruby]: contrib/lang/ruby
-[Scala]: contrib/lang/scala
-[Clojure]: contrib/lang/clojure
-[C-C++]: contrib/lang/c-c++
+[JavaScript]: contrib/!lang/javascript
+[Python]: contrib/!lang/python
+[R]: contrib/!lang/ess
+[Ruby]: contrib/!lang/ruby
+[Scala]: contrib/!lang/scala
+[Clojure]: contrib/!lang/clojure
+[C-C++]: contrib/!lang/c-c++
 [powerline-srgb-issue]: https://github.com/milkypostman/powerline/issues/54
 [powerline-doc]: doc/DOCUMENTATION.md#powerline-separators
 [so-server-unsafe]: http://stackoverflow.com/questions/885793/emacs-error-when-calling-server-start

doc/CONTRIBUTE.md

@@ -51,9 +51,9 @@ and ask your questions there. It will be a pleasure to help you to contribute!
 
 ## Submitting a configuration layer
 
-Contributed configuration layers are stored in the `contrib` folder. If the
-layer is about a programming language or script then it must be added to
-`contrib/lang` folder.
+Contributed configuration layers are stored in the `contrib` folder.
+The `contrib` folder also contains categories prefixed with `!` to put your
+layers in. For example a layer for a language would go in the `contrib/!lang` folder.
 
 It is recommended to join a `README.md` file with your layer:
 - ideally this file should document the packages of your layer as well as