Update uglifier to ~> 2.7.2

Gemfile

@@ -196,7 +196,7 @@ gem 'charlock_holmes', '~> 0.6.9.4'
 gem "sass-rails", '~> 4.0.5'
 gem "coffee-rails", '~> 4.1.0'
-gem "uglifier", '~> 2.3.2'
+gem "uglifier", '~> 2.7.2'
 gem 'turbolinks', '~> 2.5.0'
 gem 'jquery-turbolinks', '~> 2.0.1'

Gemfile.lock

@@ -741,7 +741,7 @@ GEM
       simple_oauth (~> 0.1.4)
     tzinfo (1.2.2)
       thread_safe (~> 0.1)
-    uglifier (2.3.3)
+    uglifier (2.7.2)
       execjs (>= 0.3.0)
       json (>= 1.8.0)
     underscore-rails (1.4.4)
@@ -926,7 +926,7 @@ DEPENDENCIES
   thin (~> 1.6.1)
   tinder (~> 1.10.0)
   turbolinks (~> 2.5.0)
-  uglifier (~> 2.3.2)
+  uglifier (~> 2.7.2)
   underscore-rails (~> 1.4.4)
   unf (~> 0.1.4)
   unicorn (~> 4.8.2)