.travis.yml in yq-0.3.1 vs .travis.yml in yq-0.4.0

@@ -1,7 +1,8 @@
 language: ruby
 rvm:
-  - 1.9.3
-  - 2.1.0
+  - 2.0
+  - 2.4
+  - 2.5
   - ruby-head
 # uncomment this line if your project needs to run something other than `rake`:
 script: bundle exec rspec --require spec_helper --color --format documentation spec