graphql-server-lambda has been deprecated

[mikeyhogarth]

The original library this is backed by off has been deprecated now, and replaced by a new version with a new name and I think a new API.

1. Any plans to update this library to use the new one?
2. Even if you're not updating, it might be worth updating the readme as right now you have a link to nowhere (the link to "GraphQL Lambda Server using graphql-server-lambda from Apollo." goes to a 404).

Let me know if you want a PR.