Move keyword list syntax rule into collections

Author: christopheradams

README.md

@@ -387,20 +387,6 @@ are provided here as examples of the preferred style.
  2 |> rem(3) |> g
  ```
 
-### Syntax
-
-* <a name="keyword-list-syntax"></a>
- Always use the special syntax for keyword lists.
- <sup>[[link](#keyword-list-syntax)]</sup>
-
- ```elixir
- # not preferred
- some_value = [{:a, "baz"}, {:b, "qux"}]
-
- # preferred
- some_value = [a: "baz", b: "qux"]
- ```
-
 * <a name="keyword-list-brackets"></a>
  Omit square brackets from keyword lists whenever they are optional.
  <sup>[[link](#keyword-list-brackets)]</sup>
@@ -1187,7 +1173,17 @@ directives (see [Modules](#modules)).
 
 ### Collections
 
-_No guidelines for collections have been added yet._
+* <a name="keyword-list-syntax"></a>
+ Always use the special syntax for keyword lists.
+ <sup>[[link](#keyword-list-syntax)]</sup>
+
+ ```elixir
+ # not preferred
+ some_value = [{:a, "baz"}, {:b, "qux"}]
+
+ # preferred
+ some_value = [a: "baz", b: "qux"]
+ ```
 
 ### Strings