Update documentation with arrow customization info

CHANGELOG.md

@@ -1,6 +1,13 @@
 # Change Log
 
 ## Unreleased
+
+### Added
+
+*   Add config option to customize up and down arrows used for direction indicators in the FormHelper. PR [#726](https://github.com/activerecord-hackery/ransack/pull/726)
+
+    *Garett Arrowood*
+
 ### Fixed
 
 *   Use class attributes properly so that inheritance is respected.

README.md

@@ -213,8 +213,18 @@ The sort link may be displayed without the order indicator arrow by passing
 <%= sort_link(@q, :name, hide_indicator: true) %>
 ```
 
-Alternatively, all sort links may be displayed without the order indicator arrow
-by adding this to an initializer file like `config/initializers/ransack.rb`:
+These indicator arrows may also be customized by setting them in an initializer file like `config/initializers/ransack.rb`:
+
+```ruby
+Ransack.configure do |c|
+  c.custom_arrows = {
+    up_arrow: '<i class="custom-up-arrow-icon"></i>',
+    down_arrow: 'U+02193'
+  }
+end
+```
+
+Alternatively, all sort links may be displayed without the order indicator arrows:
 
 ```ruby
 Ransack.configure do |c|

lib/ransack/configuration.rb

@@ -77,10 +77,10 @@ module Ransack
       self.options[:ignore_unknown_conditions] = boolean
     end
 
-    # Ransack's default arrows are html-code snippets found options at the
-    # top of this file. Arrows may be anything wrapped in quotation marks.
-    # Both arrows or a single arrow may be globally overridden in an
-    # initializer file like `config/initializers/ransack.rb` as follows:
+    # Ransack's default indicator arrows are html-code snippets. These
+    # arrows may be replaced by anything wrapped in quotation marks. Both
+    # or just one arrow may be globally overridden in an initializer file
+    # like `config/initializers/ransack.rb` as follows:
     #
     # Ransack.configure do |config|
     #   # Set the up_arrow as an icon, set the down arrow as unicode