code: function handlePackage(packagePath) {
    // Read in the package.json.
    var packagePath = path.join(packagePath, 'package.json');
    try {
      var package = require(packagePath);
    } catch (e) {
      console.log('Skipping package ' + packagePath);
      return;
    }
  
    // Update dependencies as appropriate.
    if (package.dependencies && target in package['dependencies']) {
      package['dependencies'][target] = specifier;
    } else if (package.devDependencies && target in package['devDependencies']) {
      package['devDependencies'][target] = specifier;
    }
  
    // Write the file back to disk.
    fs.writeFileSync(packagePath, JSON.stringify(package, null, 2) + '\n');
  }
docs: Handle an individual package on the path - update the dependency.