💄 LTS node version in `engines` (+v6.9 -v0.10) (#370)
💄 LTS node version in `engines` (+v6.9 -v0.10) (#370)

refs TryGhost/Ghost#7466

- Node v6.9 became LTS on 18th Oct
- Node v0.10 is EOL on 31st Oct
- These values are consistent with Ghost, for the v0.11 LTS stream of Ghost
- On Ghost master, these values match ember-cli
airycanon/Ghost-Admin,airycanon/Ghost-Admin