fix .travis.yml

.travis.yml

@@ -4,9 +4,10 @@ python:
 before_install:
   - "export DISPLAY=:99.0"
   - "sh -e /etc/init.d/xvfb start"
+  - sudo apt-get -qq update
+  - sudo apt-get -qq install node-less
 install:
   - "make"
-  - "node-less"
 script:
   - "make tests"
   - "make robot"