.travis.yml in cloudflare-3.1.0 vs .travis.yml in cloudflare-3.2.0

@@ -1,14 +1,18 @@
 language: ruby
 sudo: false
 dist: trusty
 cache: bundler
+
+before_script:
+  - gem update --system
+  - gem install bundler
+
 rvm:
-- 2.0
-- 2.1
-- 2.2
 - 2.3
 - 2.4
+- 2.5
+- 2.6
 - jruby-head
 - ruby-head
 matrix:
   allow_failures:
   - rvm: ruby-head