Add current and LTS Node.js versions

gpahal · gpahal · commit b2366f85feed · 2017-12-13T10:21:25.000+05:30
diff --git a/.travis.yml b/.travis.yml
@@ -1,7 +1,9 @@
 language: node_js
 node_js:
   - "node"
+  - "9"
   - "8"
+  - "6"
 sudo: required
 dist: trusty
 before_install:
