.travis.yml in m-1.4.2 vs .travis.yml in m-1.5.0

@@ -1,9 +1,11 @@
 rvm:
   - 2.0.0
   - 2.1.0
   - 2.2.0
   - jruby-1.7.21
+before_install:
+  - gem install bundler
 install:
   - bundle install
   - bundle --gemfile=gemfiles/minitest5.gemfile
   - bundle --gemfile=gemfiles/minitest4.gemfile
   - bundle --gemfile=gemfiles/test_unit_gem.gemfile