polymer live reload

package.json

// npm install browser-sync --save-dev
// npm run dev
{
  "name": "polymer-starter-kit",
  "license": "BSD-3-Clause",
  "devDependencies": {
    "browser-sync": "^2.18.8",
    "eslint": "^3.12.0",
    "eslint-config-google": "^0.7.1",
    "eslint-plugin-html": "^1.7.0"
  },
  "scripts": {
    "dev": "polymer serve | npm run watch",
    "lint": "eslint . --ext js,html --ignore-path .gitignore",
    "test": "npm run lint && polymer test",
    "watch": "browser-sync start --proxy localhost:8081 --files \"src/**/*.*, index.html, *.js\""
  }
}