[Tests] on node v8

Author: ljharb

.travis.yml

@@ -1,5 +1,6 @@
 language: node_js
 node_js:
+  - "8"
   - "7"
   - "6"
   - "5"
@@ -18,3 +19,6 @@ script:
 sudo: false
 matrix:
   fast_finish: true
+  allow_failures:
+    - node_js: "7"
+    - node_js: "5"