.travis.yml in chef-vault-2.5.0 vs .travis.yml in chef-vault-2.6.0

@@ -1,7 +1,11 @@
 language: ruby
 rvm:
   - "1.9.3-p551"
   - "2.0.0-p598"
-  - "2.1.5"
+  - "2.1.6"
+  - "2.2.2"
 install: bundle install --binstubs
 env: TRAVIS_BUILD=true
+matrix:
+  allow_failures:
+    - rvm: "1.9.3-p551"