Added unit test for building an empty stack.

This makes use of the implicit RepyNetworkAPIWrapper that sits
below the bottom of the Affix stack.
Removed outdated unit tests for old NatPunchAffix.

These need to be recreated and improved to import rather than
contain a hardcopy of the new tcp_relay code.
Moved Affix component tests to the correct dir, and removed outdated tests.
Corrected instantiation of an empty Affix stack in CoordinationAffix.
Small corrections to Affix component unit tests.

* Add timeout/exitall to openconnectioncoordinationaffix to avoid
  hangs if anything goes wrong.
* Add re-lookup to namingandresolveraffix-works as advertise
  services will need a moment or two before newly advertised
  items become available. I wonder if this is a problem we will
  start seeing with nodes even more remote than mine.