FIX: Support quarterly on user directory

app/models/directory_item.rb

@@ -13,7 +13,7 @@ class DirectoryItem < ActiveRecord::Base
   end
 
   def self.period_types
-    @types ||= Enum.new(:all, :yearly, :monthly, :weekly, :daily)
+    @types ||= Enum.new(:all, :yearly, :monthly, :weekly, :daily, :quarterly)
   end
 
   def self.refresh!
@@ -28,6 +28,7 @@ class DirectoryItem < ActiveRecord::Base
     since = case period_type
             when :daily then 1.day.ago
             when :weekly then 1.week.ago
+            when :quarterly then 3.weeks.ago
             when :monthly then 1.month.ago
             when :yearly then 1.year.ago
             else 1000.years.ago