change report time range to match actual upload formula

app/logical/reports/user_promotions.rb

@@ -38,14 +38,14 @@ module Reports
     end
 
     def self.deletion_confidence_interval_for(user, days = nil)
-      date = (days || 30).days.ago
+      date = (days || 120).days.ago
       deletions = Post.where("created_at >= ?", date).where(:uploader_id => user.id, :is_deleted => true).count
       total = Post.where("created_at >= ?", date).where(:uploader_id => user.id).count
       ci_lower_bound(deletions, total)
     end
 
     def self.negative_score_confidence_interval_for(user, days = nil)
-      date = (days || 30).days.ago
+      date = (days || 120).days.ago
       hits = Post.where("created_at >= ? and score < 0", date).where(:uploader_id => user.id).count
       total = Post.where("created_at >= ?", date).where(:uploader_id => user.id).count
       ci_lower_bound(hits, total)