.travis.yml in gibbon-3.3.1 vs .travis.yml in gibbon-3.3.2

@@ -5,6 +5,7 @@
   - gem install bundler # -v 1.7.14 if a specific version is needed
 rvm:
   - 2.3.8
   - 2.4.5
   - 2.5.7
-  - 2.6.5
\ No newline at end of file
+  - 2.6.5
+  - 2.7