language: node_js
node_js:
  - "7.8.0"
before_install:
  - npm i -g npm@5.5.1
cache:
  directories:
    - "node_modules"

language: node_js
node_js:
  - "7.8.0"
before_install:
  - npm i -g npm@5.6.0
cache:
  directories:
    - "node_modules"

Upgrade npm version in Travis CI
Upgrade npm version in Travis CI
