code: function updateAllPackages(rootPkgPath, packagesPath) {
    const paths = findPackages(packagesPath);
  
    return paths.reduce((promise, pkgPath) => promise.then(() => updateSinglePackage(rootPkgPath, pkgPath)), Promise.resolve());
  }
docs: Transforms all packages
  @param {string} rootPkgPath
  @param {string} packagesPath
  @returns {Promise}