language: node_js
node_js:
    - "6.10"
    - "5.12"
    - "4.8"

language: node_js
node_js:
    - "7.10"
    - "6.11"
    - "5.12"

Drop support for Node.js < 4
Drop support for Node.js < 4

Since v3.0.0, eslint dropped support for Node.js < 4, so do I.
