feature(typescript_indexer): add Kythe typings (#3881)
feature(typescript_indexer): add Kythe typings (#3881)

Add typings for Kythe. Ported from
[@types/kythe](https://www.npmjs.com/package/@types/kythe).

kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe