Allow typescript usage

[lucasavila00]

It solves this issue: https://github.com/dotansimha/graphql-code-generator/issues/318 To do such thing babel-extract-comments should use babylon 7.

This PR needs to be accepted first: https://github.com/jonschlinkert/babel-extract-comments/pull/4

Then this project should be updated.

Thanks for your work :)