Change prepublish to prepare

[justin808]

Per npm docs.

• https://stackoverflow.com/questions/44037774/best-practice-for-upgrading-npm-prepublish-script-for-npm-4/44136814?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa
• npm5: prepublish runs for npm install  npm/npm#16685

---

This change is