.travis.yml in patron-0.9.1 vs .travis.yml in patron-0.10.0

@@ -1,9 +1,13 @@
 rvm:
 - 1.9.3
 - 2.1.5
 - 2.2.2
-- 2.3.0
+- 2.3.4
 - 2.4.1
 sudo: false
 dist: trusty
 cache: bundler
+install:
+  - gem update --system 2.6.12  # https://github.com/rubygems/rubygems/issues/2024
+  - gem install bundler
+  - "bundle install --verbose --jobs=3 --retry=3 --path=${BUNDLE_PATH:-vendor/bundle}"