message: chore(utxo-lib): add "prepare" script in package.json
  Make sure `yarn install` at root level does the right thing
  Issue:
diff: "javascript"
  ],
  "scripts": {
  + "prepare": "npm run build",
  "build": "tsc --project tsconfig.build.json",
  "coverage-report": "nyc report --reporter=lcov",
  "coverage-html": "nyc report --reporter=html",
  