docs(faq): update compressed and minified file size


![gzip](https://f.cloud.github.com/assets/1016365/1587068/9fb1552c-5232-11e3-8aa4-66199b88e096.png)


currently the docs say <a href="http://docs.angularjs.org/misc/faq#faq_questions_whats-angulars-performance-like" target="_blank"> < 29KB</a>