update Travis

Author: jquense

.travis.yml

@@ -1,5 +1,11 @@
+sudo: false
 language: node_js
 node_js:
-  - 0.10
-before_script:                                                                                                                                 
-  - 'npm install -g karma karma-cli'  
+- 4
+cache:
+  directories:
+    - node_modules
+before_install:
+  - export CHROME_BIN=chromium-browser
+  - export DISPLAY=:99.0
+  - sh -e /etc/init.d/xvfb start