os:
  - osx
  - linux
language: node_js
node_js:
  - 7
install:
  - yarn
script:
  - yarn run ci

os:
  - osx
  - linux
language: node_js
node_js:
  - 7
  - 8
install:
  - yarn
script:
  - yarn run ci

Add node 8 to CI config.
Add node 8 to CI config.
