Multiple simultaneous instances of nmcontrol don't produce an error

[JeremyRand]

Expected behavior: running multiple instances of nmcontrol with the same data directory should result in an error.

Observed behavior: Starting multiple instances of nmcontrol doesn't produce an error. Instead, multiple python processes will exist. Sending the stop command will stop one of them; multiple stop commands are necessary to stop all of them.

I think this bug was responsible for a bug report I received regarding FreeSpeechMe.

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