.travis.yml in anycable-0.5.0 vs .travis.yml in anycable-0.5.1

@@ -5,9 +5,9 @@
 sudo: false
 
 notifications:
   email: false
 
-matrix:
-  include:
-    - rvm: 2.3.3
-    - rvm: 2.4.0
+rvm:
+  - 2.3.6
+  - 2.4.3
+  - 2.5.0