.travis.yml in upsert-2.0.4 vs .travis.yml in upsert-2.1.0

@@ -1,11 +1,15 @@
 language: ruby
 global:
   - USERNAME=travis
     PASSWORD=
 rvm:
+  - 2.2.0
+  - 2.1.0
+  - 2.0.0
   - 1.9.3
   - 1.9.2
   - 1.8.7
+  - rbx-2
 env:
   - DB=postgresql
   - DB=mysql