ACL type is missing grants and IP sets fields

[matshch]

With the release of IP sets to GA and grants to beta (https://tailscale.com/blog/via) it would be great to have ACL type updated to reflect these features.

I can bring PR with my understanding of how these fields should look like, but I guess you might have these types in internal codebase and would like to bring them here as is.

[clstokes]

This has been implemented in the v2 client.

This repo and client is now deprecated (see #133). Please migrate to the v2 client.