chore: upgrade deps

Author: freaktechnik

.travis.yml

@@ -1,7 +1,4 @@
 sudo: false
 language: node_js
 node_js: stable
-before_install: npm i -g greenkeeper-lockfile
-before_script: greenkeeper-lockfile-update
-after_script: greenkeeper-lockfile-upload
 after_success: npm run coverage