Add sidetiq to gemfile.

Gemfile

@@ -114,6 +114,7 @@ gem "acts-as-taggable-on"
 gem 'slim'
 gem 'sinatra', require: nil
 gem 'sidekiq', '2.17.0'
+gem 'sidetiq', '0.6.1'
 
 # HTTP requests
 gem "httparty"

Gemfile.lock

@@ -252,6 +252,7 @@ GEM
       multi_xml (>= 0.5.2)
     httpauth (0.2.1)
     i18n (0.6.11)
+    ice_cube (0.12.1)
     ice_nine (0.10.0)
     jasmine (2.0.2)
       jasmine-core (~> 2.0.0)
@@ -477,6 +478,10 @@ GEM
       json
       redis (>= 3.0.4)
       redis-namespace (>= 1.3.1)
+    sidetiq (0.6.1)
+      celluloid (>= 0.14.1)
+      ice_cube (~> 0.12.0)
+      sidekiq (>= 2.16.0)
     simple_oauth (0.1.9)
     simplecov (0.9.0)
       docile (~> 1.1.0)
@@ -686,6 +691,7 @@ DEPENDENCIES
   settingslogic
   shoulda-matchers (~> 2.1.0)
   sidekiq (= 2.17.0)
+  sidetiq (= 0.6.1)
   simplecov
   sinatra
   six