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>)
# module which import C files as stringsimport osfrom PLCObject import PLCObject, PLCprintimport ServicePublisher