language: ruby
rvm:
  - 2.2.6
  - 2.3.3
  - 2.4.0
  - jruby-9.1.8.0

matrix:
  allow_failures:
    - rvm:
        - ruby-head
        - rbx-2

language: ruby
rvm:
  - 2.2.7
  - 2.3.4
  - 2.4.1
  - jruby-9.1.8.0

matrix:
  allow_failures:
    - rvm:
        - ruby-head
        - rbx-2

Update Ruby (MRI) versions to latest for Travis CI config
Update Ruby (MRI) versions to latest for Travis CI config

[2.2.7](https://www.ruby-lang.org/en/news/2017/03/28/ruby-2-2-7-released/)

[2.3.4](https://www.ruby-lang.org/en/news/2017/03/30/ruby-2-3-4-released/)

[2.4.1](https://www.ruby-lang.org/en/news/2017/03/22/ruby-2-4-1-released/)
