Optional config directory, verbose exceptions
splitter, worker, collector: process --help
Refactoring gns.plugins: pep8
gns.service.init(): print short message and exit when configuration is incorrect
gns.service: disable validation for core.rules-dir
gns-reinit, gns-fetch-rules: replaced --do-it-now RuntimeError to argparse logic
gns.service: yaml.load takes stream
gns.service: verbose messages in _load_configs()
Merge pull request #60 from mdevaev/optparser-fixes

Optparser fixes