* Fix for relay migration on rehandshaking issue. On rehandshake, the relay tunnel doesn't migrate to the new hostinfo object correctly, due to an incorrect Nebula IP sent in the CreateRelayRequest message.
* Add a test for this case
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Co-authored-by: Nate Brown <nbrown.us@gmail.com>
These new helpers make the code a lot cleaner. I confirmed that the
simple helpers like `atomic.Int64` don't add any extra overhead as they
get inlined by the compiler. `atomic.Pointer` adds an extra method call
as it no longer gets inlined, but we aren't using these on the hot path
so it is probably okay.
