TESTS: add support for travis on node 8 and 9

AJ Keller · AJ Keller · commit 091d8408ee22 · 2018-03-08T11:56:02.000-05:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,9 +1,10 @@
 language: node_js
 node_js:
   - "4.8.4"
-  - "6.11.1"
-  - "7.10.1"
-  - "8.1.4"
+  - "6"
+  - "7"
+  - "8"
+  - "9"
 install:
   - npm install --all
 script:
