language: ruby
bundler_args: --without development
rvm:
  - 2.1.8
  - 2.2.4
  - 2.3.0

before_install:
  - gem update --system $gemver
  - gem --version

env:
  - gemver: 2.5.2


language: ruby
bundler_args: --without development
rvm:
  - 2.2.*
  - 2.3.*
  - 2.4.*

before_install:
  - gem update --system $gemver
  - gem --version

env:
  - gemver: 2.6.13

Drop ruby 2.1 and add 2.4. Upgrade gem version
Drop ruby 2.1 and add 2.4. Upgrade gem version
