fix pyZeroconf bug where getServiceInfo returns None.
This allows the discovery window to work with targets using Avahi to advertise their services.
(patch obtained from <http://sourceforge.net/tracker/?func=detail&aid=1600775&group_id=100909&atid=628622>)

import time,sys
def myprintfunc(arg):
    print arg
    sys.stdout.flush()
    return arg