.travis.yml in tty-table-0.6.0 vs .travis.yml in tty-table-0.7.0

@@ -4,12 +4,13 @@
 cache: bundler
 bundler_args: --without yard benchmarks
 script: "bundle exec rake ci"
 rvm:
   - 2.0.0
-  - 2.1.0
-  - 2.2.5
-  - 2.3.1
+  - 2.1.10
+  - 2.2.6
+  - 2.3.3
+  - 2.4.0
   - ruby-head
   - jruby-9.1.1.0
   - jruby-head
 matrix:
   allow_failures: