.travis.yml in countries-1.2.2 vs .travis.yml in countries-1.2.4

@@ -1,6 +1,11 @@
 sudo: false
 cache: bundler
+language: ruby
 rvm:
  - 1.9.3
  - 2.0.0
  - 2.2.3
+ - ruby-head
+matrix:
+  allow_failures:
+    - rvm: ruby-head