Add node-v6 in TravisCI 🎉

.travis.yml

@@ -14,6 +14,7 @@ node_js:
   - '0'
   - 4
   - 5
+  - 6
 before_script:
   - npm prune
 script:
@@ -35,4 +36,4 @@ deploy:
   api_key:
     secure: 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
   on:
-    node: 5
+    node: 6