Add pagination by max_id instead of offset/limit

lib/tasks/feeds.rake

@@ -0,0 +1,8 @@
+namespace :feeds do
+
+  desc "Removes all feeds from Redis, forcing a precompute on next request for each user"
+  task clear: :environment do
+    $redis.keys('feed:*').each { |key| $redis.del(key) }
+  end
+
+end