ci: run travis on new node lts -> v10

Hotell · Hotell · commit af7bcbc9091d · 2019-01-14T08:00:42.000+01:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,5 +1,7 @@
 language: node_js
-node_js: '8'
+node_js:
+  - '8'
+  - '10'
 cache: yarn
 notifications:
   email: false
