language: ruby
rvm:
 - 1.9.3-p551
 - 2.0.0-p648
 - 2.1.8
 - 2.2.4
 - 2.3.0
 - 2.4.0
script: bundle exec rake

language: ruby
rvm:
 - 2.1.8
 - 2.2.4
 - 2.3.0
 - 2.4.0
script: bundle exec rake

Remove 1.9 and 2.0 from the build matrix
Remove 1.9 and 2.0 from the build matrix

Upstream has stopped supporting Ruby 2.0 more than a year ago.

This change is mostly triggered by recent rubocop rejecting the versions,
but it seems like a good idea to stop worrying about them anyway.
