Support for `value_list` in site settings

app/assets/javascripts/admin/components/site-setting.js.es6

@@ -4,7 +4,7 @@ import SiteSetting from 'admin/models/site-setting';
 import { propertyNotEqual } from 'discourse/lib/computed';
 import computed from 'ember-addons/ember-computed-decorators';
 
-const CustomTypes = ['bool', 'enum', 'list', 'url_list', 'host_list', 'category_list'];
+const CustomTypes = ['bool', 'enum', 'list', 'url_list', 'host_list', 'category_list', 'value_list'];
 
 export default Ember.Component.extend(BufferedContent, ScrollTop, {
   classNameBindings: [':row', ':setting', 'setting.overridden', 'typeClass'],

app/assets/javascripts/admin/templates/components/site-settings/value-list.hbs

@@ -0,0 +1,3 @@
+{{value-list values=value}}
+{{setting-validation-message message=validationMessage}}
+<div class='desc'>{{{unbound setting.description}}}</div>

lib/site_setting_extension.rb

@@ -21,7 +21,18 @@ module SiteSettingExtension
   end
 
   def types
-    @types ||= Enum.new(:string, :time, :fixnum, :float, :bool, :null, :enum, :list, :url_list, :host_list, :category_list)
+    @types ||= Enum.new(:string,
+                        :time,
+                        :fixnum,
+                        :float,
+                        :bool,
+                        :null,
+                        :enum,
+                        :list,
+                        :url_list,
+                        :host_list,
+                        :category_list,
+                        :value_list)
   end
 
   def mutex