Test against ruby 2.2.4

amatsuda · amatsuda · commit 482cab3acdfd · 2015-12-19T06:45:40.000+09:00
diff --git a/.travis.yml b/.travis.yml
@@ -5,7 +5,7 @@ rvm:
   - 1.9.3
   - 2.0.0
   - 2.1
-  - 2.2.3
+  - 2.2.4
   - ruby-head
 
 gemfile:
