Better naming of IP address related variables in Beremiz_service.py, Ignore errors that occur on shutdown in Zeroconf.py, fixed discovery dialog crash due to asynchronous call from zeroconf

To generate message.pot file:

	python mki18n.py -p --domain=Beremiz
	
To generate .mo files for all languages:

	python mki18n.py -m --moTarget=../locale --domain=Beremiz