Consider upstreaming iOS and macOS support to ipasn/go-libtor

[hellais]

First, thanks so much for putting in the effort to add support for iOS and macOS it's very much appreciated!

We are considering using this library for integrating tor into our own app (ooni/probe) and stumbled into this.

I noticed in the readme you mentioned that you decided to just fork the project because ipasn/go-libtor looked abbandoned, but I see that there is some recent activity over there.

There is also clearly interest in having iOS and macOS support in the upstream version of the library too.

Would you consider contributing the changes back to the upstream so the maintenance effort can be consolidated in a single repo?

@karalabe do you see any issues with upstreaming the changes from this library?