code: function addModulesToPackageJson(externalModules, packageJson, pathToPackageRoot) {
    _.forEach(externalModules, externalModule => {
      const splitModule = _.split(externalModule, '@');
      // If we have a scoped module we have to re-add the @
      if (_.startsWith(externalModule, '@')) {
        splitModule.splice(0, 1);
        splitModule[0] = '@' + splitModule[0];
      }
      let moduleVersion = _.join(_.tail(splitModule), '@');
      // We have to rebase file references to the target package.json
      moduleVersion = rebaseFileReferences(pathToPackageRoot, moduleVersion);
      packageJson.dependencies = packageJson.dependencies || {};
      packageJson.dependencies[_.first(splitModule)] = moduleVersion;
    });
  }
docs: Add the given modules to a package json's dependencies.