Added angular.js 1.2.21

I added angular files. I copied the files from https://github.com/angular/bower-*

Sorry not to use auto update here, but seems the autoupdate can have only one repository per lib/package. The current structure in cdnjs is different from angular's structure, which makes it harder to keep the same. An option would be create new "projects" on cdnjs for each of these angular's bower projects.