language: ruby
rvm:
  - 2.0.0
  - 2.1.10
  - 2.2.6
  - 2.3.3
  - 2.4.0
  - ruby-head
before_install:
  - gem update --system
  - gem install bundler -v 1.11.2

language: ruby
rvm:
  - 2.0.0
  - 2.1.10
  - 2.2.7
  - 2.3.3
  - 2.4.1
  - ruby-head
before_install:
  - gem update --system
  - gem install bundler -v 1.11.2

Update Ruby version on Travis CI
Update Ruby version on Travis CI
