Fix sprockets error

Gemfile

@@ -5,6 +5,7 @@ ruby '2.1.5'
 
 gem 'rails', "= 3.2.11"
 gem 'sass-rails'
+gem "sprockets", ">= 2.2.2"
 
 # API
 gem 'sinatra', "= 1.2.7"
@@ -100,7 +101,7 @@ gem 'km', '= 1.1.2'
 gem 'km-db', :git => "https://github.com/Jberlinsky/km-db.git", :ref => "65bf2c5ffc203a773c9cc2d491306924a6c78cd2"
 
 group :assets do
-  gem 'uglifier', '= 1.2.3'
+  gem 'uglifier'
 end
 
 group :development do
@@ -147,7 +148,6 @@ gem 'rack', '= 1.4.5'
 gem 'rack-ssl', '= 1.3.2'
 gem 'rack-test', '= 0.6.1'
 gem 'rake', '= 0.9.2.2'
-gem 'sprockets', '= 2.2.1'
 gem 'treetop', '= 1.4.10'
 gem 'tzinfo', '= 0.3.32'
 gem 'area', '= 0.9.0', :require => false

Gemfile.lock

@@ -205,7 +205,7 @@ GEM
     escape (0.0.4)
     eventmachine (1.0.3)
     excon (0.15.5)
-    execjs (2.0.2)
+    execjs (2.6.0)
     factory_girl (2.6.3)
       activesupport (>= 2.3.9)
     faraday (0.7.6)
@@ -448,7 +448,7 @@ GEM
       tilt (>= 1.2.2, < 2.0)
     slop (3.5.0)
     spork (0.9.2)
-    sprockets (2.2.1)
+    sprockets (2.2.3)
       hike (~> 1.2)
       multi_json (~> 1.0)
       rack (~> 1.0)
@@ -476,9 +476,9 @@ GEM
       polyglot (>= 0.3.1)
     trollop (1.16.2)
     tzinfo (0.3.32)
-    uglifier (1.2.3)
+    uglifier (2.2.1)
       execjs (>= 0.3.0)
-      multi_json (>= 1.0.2)
+      multi_json (~> 1.0, >= 1.0.2)
     vegas (0.1.11)
       rack (>= 1.0.0)
     warden (1.1.1)
@@ -581,12 +581,12 @@ DEPENDENCIES
   simplecov (= 0.6.4)
   sinatra (= 1.2.7)
   spork (= 0.9.2)
-  sprockets (= 2.2.1)
+  sprockets (>= 2.2.2)
   sunspot_rails (= 1.3.0)
   sunspot_solr (= 1.3.0)
   thin (= 1.3.1)
   treetop (= 1.4.10)
   trollop (= 1.16.2)
   turing-contacts!
   tzinfo (= 0.3.32)
-  uglifier (= 1.2.3)
+  uglifier