chore: use default travis distro

Author: bennypowers

.travis.yml

@@ -1,7 +1,6 @@
 language: node_js
 node_js:
-  - "node"
-dist: trusty
+  - node
 addons:
   apt:
     packages:
@@ -25,4 +24,4 @@ deploy:
   keep-history: true
   target-branch: master
   on:
-    branch: dev
+    branch: dev