Fix for issue 3616 "View source" link on docs is broken

This solves Issue https://github.com/angular/angular.js/issues/3616

"View source" link on docs is broken because it references undefined property gruntUtil.getVersion().number.

I've changed two references to instead use gruntUtil.getVersion().cdnVersion, which presently contains an appropriate string (a git tag) for linking to documentation.

(If this is not an acceptable version property to reference, perhaps there is a better one? Or, as a temporary fix perhaps we should just link to the "master" code source instead of the grunt version tagged source file.)