sudo: false
language: ruby
rvm:
  - 2.0.0
  - 2.1.10
  - 2.2.6
  - 2.3.3
  - 2.4.0
before_install: gem install bundler -v 1.13.6

sudo: false
language: ruby
rvm:
  - 2.0.0
  - 2.1.10
  - 2.2.6
  - 2.3.3
  - 2.4.0
before_install:
  - gem update --system
  - gem install bundler -v 1.13.6

Update gem to the latest version to fix build error
Update gem to the latest version to fix build error

https://travis-ci.org/emsk/backlog_kit/jobs/200349504
