Add six

.travis.yml

@@ -11,7 +11,7 @@ go:
 
 before_script:
   - sudo apt-get install -y libjna-java python-pip
-  - sudo pip install cql PyYAML
+  - sudo pip install cql PyYAML six
   - go get code.google.com/p/go.tools/cmd/vet
   - git clone https://github.com/pcmanus/ccm.git
   - pushd ccm