Use node_js instead of node

alanpoulain · alanpoulain · commit cbf0c353f1b1 · 2018-10-06T18:11:33.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,4 +1,6 @@
-language: node
+language: node_js
+node_js:
+  - '6'
 
 cache:
   yarn: true
