Upgrade omniauth to version 1.8.1

Gemfile

@@ -29,7 +29,7 @@ gem 'jquery-rails', '~> 4.3.1'
 gem 'jquery-ui-rails', '~> 6.0.1'
 gem 'kaminari', '~> 1.0.1'
 gem 'newrelic_rpm', '~> 4.1.0.333'
-gem 'omniauth', '~> 1.6.1'
+gem 'omniauth', '~> 1.8.1'
 gem 'omniauth-facebook', '~> 4.0.0'
 gem 'omniauth-google-oauth2', '~> 0.4.0'
 gem 'omniauth-twitter', '~> 1.4.0'

Gemfile.lock

@@ -182,7 +182,7 @@ GEM
       activesupport (>= 3)
     gyoku (1.3.1)
       builder (>= 2.1.2)
-    hashie (3.5.5)
+    hashie (3.5.7)
     highline (1.7.10)
     htmlentities (4.3.4)
     httpi (2.4.2)
@@ -275,7 +275,7 @@ GEM
       multi_json (~> 1.3)
       multi_xml (~> 0.5)
       rack (>= 1.2, < 3)
-    omniauth (1.6.1)
+    omniauth (1.8.1)
       hashie (>= 3.4.6, < 3.6.0)
       rack (>= 1.6.2, < 3)
     omniauth-facebook (4.0.0)
@@ -534,7 +534,7 @@ DEPENDENCIES
   letter_opener_web (~> 1.3.1)
   mdl (~> 0.4.0)
   newrelic_rpm (~> 4.1.0.333)
-  omniauth (~> 1.6.1)
+  omniauth (~> 1.8.1)
   omniauth-facebook (~> 4.0.0)
   omniauth-google-oauth2 (~> 0.4.0)
   omniauth-twitter (~> 1.4.0)