.travis.yml in critic-0.2.2 vs .travis.yml in critic-0.2.3

@@ -1,15 +1,19 @@
 language: ruby
 sudo: false
+before_install:
+  - gem install -v 1.13.6 bundler --no-document
+  - gem install -v 1.17.3 bundler --no-document
 cache:
   - bundler
 rvm:
   - 2.3.0
 script:
   - bundle exec rake rubocop
   - bundle exec rake spec
 notifications:
   email: false
 gemfile:
+  - gemfiles/activesupport_5_2.gemfile
   - gemfiles/activesupport_5.gemfile
   - gemfiles/activesupport_4.gemfile
   - gemfiles/activesupport_3.gemfile