Revert "Clean up elixir layer documentation"

This reverts commit 333e921707.

layers/+lang/elixir/README.org

@@ -7,6 +7,7 @@
 - [[#install][Install]]
 - [[#configuration][Configuration]]
   - [[#flycheck][Flycheck]]
+    - [[#credo][Credo]]
     - [[#dogma][Dogma]]
     - [[#mix-compile][mix compile]]
 - [[#key-bindings][Key bindings]]
@@ -37,6 +38,8 @@ like:
 - Elixir project management
 - Integration with [[http://company-mode.github.io/][company-mode]]
 - Flycheck support for mix compile
+- Flycheck support for [[https://github.com/rrrene/credo][credo]]
+- Flycheck support for test results
 
 * Install
 To use this configuration layer, add it to your =~/.spacemacs=. You will need to
@@ -48,6 +51,28 @@ file.
 *Note:* since flycheck checkers are slow, the checks are enabled only at save
 time.
 
+*** Credo
+You need to install [[https://github.com/rrrene/credo][credo]] into your project. For this, add the following snippet
+to dependencies of your project (in file =mix.exs=):
+
+#+BEGIN_SRC
+{:credo, "~> 0.5", only: [:dev, :test]}
+#+END_SRC
+
+Then run in your shell:
+
+#+BEGIN_SRC shell
+$ mix deps.get
+#+END_SRC
+
+For more info about mix [[http://elixir-lang.org/getting-started/mix-otp/introduction-to-mix.html][see]].
+
+You can tell flycheck-credo to call credo with the '--strict' argument.
+
+#+BEGIN_SRC elisp
+(setq flycheck-elixir-credo-strict t)
+#+END_SRC
+
 *** Dogma
 In order to lint your code, you also need to install [[https://github.com/lpil/dogma][dogma]] into your project.
 For this, add the following snippet to the dependencies in your =mix.exs= file: