.travis.yml in rspreadsheet-0.2.14 vs .travis.yml in rspreadsheet-0.2.15

@@ -5,9 +5,11 @@
   - 2.2.0
   - 2.1.7
   - 2.0.0
   - 1.9.3
 script: 'bundle exec rake'
+before_install:
+  - gem update bundler
 notifications:
   email:
     recipients:
       - [e-mail]
     on_failure: change
\ No newline at end of file