Update dependencies (#20)

* npm update

* npx npm-check-updates -u && npm install

* Require Node >=10

Author: michielbdejong

.travis.yml

@@ -1,7 +1,6 @@
 sudo: false
 language: node_js
 node_js:
-  - "8"
   - "10"
   - "lts/*"
   - "node"