Bump rack from 1.6.4 to 2.2.3

Gemfile.lock

@@ -1,27 +1,27 @@
 GEM
   remote: http://rubygems.org/
   specs:
-    addressable (2.4.0)
+    addressable (2.7.0)
+      public_suffix (>= 2.0.2, < 5.0)
     builder (3.2.2)
     descendants_tracker (0.0.4)
       thread_safe (~> 0.3, >= 0.3.1)
     diff-lcs (1.2.5)
-    faraday (0.9.2)
+    faraday (1.0.1)
       multipart-post (>= 1.2, < 3)
     git (1.2.9.1)
     github-markup (1.4.0)
-    github_api (0.13.1)
-      addressable (~> 2.4.0)
+    github_api (0.19.0)
+      addressable (~> 2.4)
       descendants_tracker (~> 0.0.4)
-      faraday (~> 0.8, < 0.10)
-      hashie (>= 3.4)
-      multi_json (>= 1.7.5, < 2.0)
-      oauth2
+      faraday (>= 0.8, < 2)
+      hashie (~> 3.5, >= 3.5.2)
+      oauth2 (~> 1.0)
     glib2 (3.0.7)
       pkg-config
     gobject-introspection (3.0.7)
       glib2 (= 3.0.7)
-    hashie (3.4.3)
+    hashie (3.6.0)
     highline (1.7.8)
     jeweler (2.0.1)
       builder
@@ -33,21 +33,22 @@ GEM
       rake
       rdoc
     json (1.8.3)
-    jwt (1.5.2)
+    jwt (2.2.2)
     mini_portile2 (2.0.0)
-    multi_json (1.11.2)
-    multi_xml (0.5.5)
-    multipart-post (2.0.0)
+    multi_json (1.15.0)
+    multi_xml (0.6.0)
+    multipart-post (2.1.1)
     nokogiri (1.6.7.2)
       mini_portile2 (~> 2.0.0.rc2)
-    oauth2 (1.0.0)
-      faraday (>= 0.8, < 0.10)
-      jwt (~> 1.0)
+    oauth2 (1.4.4)
+      faraday (>= 0.8, < 2.0)
+      jwt (>= 1.0, < 3.0)
       multi_json (~> 1.3)
       multi_xml (~> 0.5)
-      rack (~> 1.2)
+      rack (>= 1.2, < 3)
     pkg-config (1.1.7)
-    rack (1.6.4)
+    public_suffix (4.0.6)
+    rack (2.2.3)
     rake (10.5.0)
     rdoc (4.2.1)
       json (~> 1.4)
@@ -65,7 +66,7 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.4.0)
     rspec-support (3.4.1)
-    thread_safe (0.3.5)
+    thread_safe (0.3.6)
     yard (0.8.7.6)
 
 PLATFORMS