Travis: removed node 6 which is not provided yet

Joel Mukuthu · Joel Mukuthu · commit 42320f548ef0 · 2016-05-23T19:36:26.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -4,6 +4,5 @@ node_js:
   - '0.12'
   - '4'
   - '5'
-  - '6'
 before_script:
   - 'npm install -g bower grunt-cli'
