.travis.yml in gibbon-3.3.0 vs .travis.yml in gibbon-3.3.1

@@ -2,10 +2,9 @@
 sudo: false
 cache: bundler
 before_install:
   - gem install bundler # -v 1.7.14 if a specific version is needed
 rvm:
-  - 2.1.5
-  - 2.2.2
   - 2.3.8
   - 2.4.5
-  - 2.5.3
+  - 2.5.7
+  - 2.6.5
\ No newline at end of file