language: ruby
sudo: false
cache: bundler
rvm:
  - 2.2.5
  - 2.3.1

language: ruby
sudo: false
cache: bundler
rvm:
  - 2.2.6
  - 2.3.3
  - 2.4.0

Update Ruby versions and add 2.4.0.
Update Ruby versions and add 2.4.0.
