Test telnet server close

[icing]

Slight change in test telnet server code to have it invoke its close() method.

[bagder]

This round at least didn't cause any telnet issues. Should we re-run any particular test a few times to be more sure or do you think this is likely to actually be the proper fix?

[icing]

In any case, it is a better test code as it calls close() on the server object, as an application is expected to. I could imagine the Python internals to abort sockets not properly closed in deconstruction. But I have not checked.

I have locally not seen the telnet test fails on my mac with this change. I'd say, merge it and we revisit should we see another telnet CONNRESET failure.

[bagder]

Excellent, thanks!