Fix TCP connections on python 2

[embray]

On python 2 socket.create_connection requires the port to be an int.

I'm not overly concerned about Python 2 support. Indeed I'm mostly using Python 3. I just happened to hit on this while testing some other code on Python 2.

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[embray]

I signed it!

[coveralls]

Coverage decreased (-0.04%) to 43.531% when pulling 4bcf757 on embray:python2/tcp-port into d9b94b2 on google:master.

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