Fit and finish baton app

[huitema]

From the early test, three small fixes needed:

1) Fix unused variables warning in unix builds

2) Add some execution reporting in the bacon app: how many turns, what was the final error code, how many datagrams were received, etc.

3) Fix the race condition on FIN in the baton app -- should not exit if the client has not actually sent the close message, or received a close message from the server.

[huitema]

Much of that has been done. The one piece that remains: running multiple batons in parallel. This needs discussion...

[huitema]

Fixed in PR #1475