If you will be in sync with the last version of the project you can use:
jQuery latest: http://code.jquery.com/jquery-latest.min.js
Angular: http://code.angularjs.org/snapshot/angular.min.js
...
Google CDN doesn't implement this latest feature.
If you want to update versions by yourself you can use a template render in your grunt build process. https://www.npmjs.org/package/grunt-mustache-render for example. Keep a config file with versions per library and a template with your file and the gaps to be rendered in the html file.