Add the sidekiq-failures gem so that we can diagnose failed jobs

Gemfile

@@ -59,6 +59,7 @@ gem 'sanitize'
 gem 'sass'
 gem 'seed-fu'
 gem 'sidekiq'
+gem 'sidekiq-failures'
 gem 'sinatra', require: nil
 gem 'slim'  # required for sidekiq-web
 gem 'strong_parameters' # remove when we upgrade to Rails 4

Gemfile.lock

@@ -422,6 +422,11 @@ GEM
       multi_json (~> 1)
       redis (~> 3)
       redis-namespace
+    sidekiq-failures (0.1.0)
+      sidekiq (>= 2.2.1)
+      sinatra
+      slim
+      sprockets
     simplecov (0.7.1)
       multi_json (~> 1.0)
       simplecov-html (~> 0.7.1)
@@ -544,6 +549,7 @@ DEPENDENCIES
   seed-fu
   shoulda
   sidekiq
+  sidekiq-failures
   simple_handlebars_rails!
   simplecov
   sinatra

lib/jobs/clockwork_heartbeat.rb

@@ -1,6 +1,8 @@
 module Jobs
   class ClockworkHeartbeat < Jobs::Base
 
+    sidekiq_options retry: false
+
     def execute(args)
       $redis.set last_heartbeat_at_key, Time.now.to_i
     end